JP2007157704A - Negative electrode for coin type lithium secondary battery, its manufacturing method, and coin type lithium secondary battery - Google Patents

Negative electrode for coin type lithium secondary battery, its manufacturing method, and coin type lithium secondary battery Download PDF

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JP2007157704A
JP2007157704A JP2006304152A JP2006304152A JP2007157704A JP 2007157704 A JP2007157704 A JP 2007157704A JP 2006304152 A JP2006304152 A JP 2006304152A JP 2006304152 A JP2006304152 A JP 2006304152A JP 2007157704 A JP2007157704 A JP 2007157704A
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negative electrode
molded body
coin
molded
lithium secondary
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Teruaki Yamamoto
輝明 山本
Tomohiro Ueda
智博 植田
Yoko Sano
陽子 佐野
Yasuhiko Mifuji
靖彦 美藤
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Panasonic Holdings Corp
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Matsushita Electric Industrial Co Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

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Abstract

<P>PROBLEM TO BE SOLVED: To suppress capacity deterioration of a lithium secondary battery by stabilizing the structure of a negative electrode molding. <P>SOLUTION: A coin type lithium secondary battery contains a positive electrode, a positive can for housing the positive electrode, a negative electrode, a negative can for housing the negative electrode, and a separator interposed between the positive electrode and the negative electrode. The negative electrode contains a negative molding containing a negative active material for absorbing and releasing lithium, and the negatived molding is a coin type having two plane surfaces and a side surface, and has cracks in the thickness direction. When at least one of two plane surfaces has a recessed part, the starting point of cracks is the recessed part, and when the negative can has a projection part on the surface facing the negative molding, the starting point of the cracks is a contact part between the projection part and the negative molding. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、コイン型リチウム二次電池に関し、特にコイン型リチウム二次電池用負極とその製造方法に関する。   The present invention relates to a coin-type lithium secondary battery, and more particularly, to a negative electrode for a coin-type lithium secondary battery and a method for manufacturing the same.

リチウム二次電池は、起電力が高く、高エネルギー密度であるという特長を有する。リチウム二次電池は、移動体通信機器および携帯電子機器の主電源として利用されている他、メモリーバックアップ用電源としての需要も年々増加している。さらに、携帯型の電子機器等の著しい発展に伴い、機器の更なる小型化、高性能化およびメンテナンスフリー化等の観点から、高エネルギー密度のリチウム二次電池が強く要望されている。   A lithium secondary battery has a feature of high electromotive force and high energy density. Lithium secondary batteries are used as a main power source for mobile communication devices and portable electronic devices, and demand for memory backup power sources is increasing year by year. Furthermore, with the remarkable development of portable electronic devices and the like, there is a strong demand for lithium secondary batteries with high energy density from the viewpoints of further miniaturization, high performance, and maintenance-free devices.

そこで、リチウム二次電池の高容量化を図るため、炭素材料よりも理論容量の大きい負極材料であるＳｉ系材料およびＳｎ系材料が注目されている。しかし、結晶質状態のＳｉおよびＳｎは、充放電時にリチウム（イオン）を吸蔵および放出する際、膨張と収縮により、最大で４倍程度の体積変化を起こす。そのため、体積変化による歪みを受けて、ＳｉおよびＳｎが微粉化し、負極構造が破壊される。また、Ｓｉ自体は電子伝導度が低いため、これを含むリチウム二次電池は、従来と比較して、サイクル寿命特性やレート特性が顕著に低下する。ここで、負極は、一般に、活物質、導電剤、結着剤などを含む合剤からなる。   Therefore, in order to increase the capacity of lithium secondary batteries, Si-based materials and Sn-based materials, which are negative electrode materials having a larger theoretical capacity than carbon materials, are attracting attention. However, Si and Sn in a crystalline state cause a volume change of up to about 4 times due to expansion and contraction when inserting and extracting lithium (ions) during charge and discharge. Therefore, Si and Sn are pulverized due to distortion due to volume change, and the negative electrode structure is destroyed. In addition, since Si itself has low electronic conductivity, the cycle life characteristics and rate characteristics of a lithium secondary battery including the Si remarkably deteriorate as compared with the related art. Here, the negative electrode is generally composed of a mixture containing an active material, a conductive agent, a binder and the like.

そこで、遷移金属などの他元素をＳｉに添加した合金を活物質に用いることが提案されている。このような合金は、Ｓｉ相とＳｉと遷移金属との合金相とを含む。これらの相の結晶子サイズ（crystallite size）を制御することにより、活物質の体積変化を緩和することができる（例えば特許文献１）。   Therefore, it has been proposed to use an alloy in which other elements such as transition metals are added to Si as an active material. Such an alloy includes an Si phase and an alloy phase of Si and a transition metal. By controlling the crystallite size of these phases, the volume change of the active material can be relaxed (for example, Patent Document 1).

また、表面を粗化した集電体の上に活物質の薄膜を形成するとともに、充電時の体積膨脹による応力以上の強度を集電体に持たせることが提案されている。初回の体積膨脹による応力により、薄膜は複数の柱状部を生成する。その結果、以降の充放電時の体積変化による応力を緩和できるようになり、集電体と活物質との密着性を保持することができる（例えば特許文献２）。   In addition, it has been proposed to form a thin film of an active material on a current collector having a roughened surface, and to give the current collector strength higher than the stress due to volume expansion during charging. The thin film generates a plurality of columnar portions due to the stress due to the first volume expansion. As a result, it becomes possible to relieve the stress due to the volume change during the subsequent charge / discharge, and the adhesion between the current collector and the active material can be maintained (for example, Patent Document 2).

更に、マスクを利用して、集電体上に所定のパターンで活物質と空隙とを設け、空隙により応力緩和を可能にし、充放電の繰り返しによる電極劣化を抑制することが提案されている（例えば特許文献３）。
特開２００４−１０３３４０号公報 特開２００２−２６０６３７号公報 特開２００４−１０３４７４号公報 Furthermore, it has been proposed to use a mask to provide an active material and voids in a predetermined pattern on a current collector, to enable stress relaxation by the voids, and to suppress electrode deterioration due to repeated charge and discharge ( For example, Patent Document 3).
JP 2004-103340 A Japanese Patent Laid-Open No. 2002-260637 JP 2004-103474 A

特許文献１の活物質を用いて負極を作製した場合、活物質の微粉化は抑制できる。しかし、活物質の体積膨張が大きいため、負極の構造を保持することは困難である。
特許文献２の負極は、初回の応力に耐えるためには、集電体の厚さを薄膜の厚さと同等にすることが必要となる。よって、負極全体の大幅な容量増加は見込めない。
特許文献３の負極は、微細なパターンによるマスクの形成工程と、その除去工程が必要であるため、現実的ではない。 When a negative electrode is manufactured using the active material of patent document 1, pulverization of an active material can be suppressed. However, since the volume expansion of the active material is large, it is difficult to maintain the negative electrode structure.
In order for the negative electrode of Patent Document 2 to withstand the initial stress, the thickness of the current collector needs to be equal to the thickness of the thin film. Therefore, a significant increase in capacity of the entire negative electrode cannot be expected.
The negative electrode of Patent Document 3 is not realistic because it requires a mask formation process with a fine pattern and a removal process thereof.

本発明は、高容量化が可能な活物質を用いつつ、負極の体積膨張を緩和し、負極構造の保持を図り、電池容量の劣化を抑制することを目的とする。   An object of the present invention is to reduce the volume expansion of the negative electrode, maintain the negative electrode structure, and suppress the deterioration of the battery capacity while using an active material capable of increasing the capacity.

本発明者らは、鋭意検討の結果、コイン型リチウム二次電池において、コイン型の負極成型体を一定の大きさに積極的に分割することにより、その後の負極の形状維持が良好となり、負極の厚さ方向における集電経路の断絶が緩和されることを見出した。本発明は、この知見に基づくものであり、コイン型の負極成型体に、厚さ方向の亀裂を形成することにより、負極成型体の分割を積極的に誘起し、更には、分割の仕方を制御する。   As a result of intensive studies, the inventors of the present invention have succeeded in positively maintaining the shape of the negative electrode by actively dividing the coin-shaped negative electrode molded body into a certain size in a coin-type lithium secondary battery. It was found that the disconnection of the current collection path in the thickness direction of the wall was alleviated. The present invention is based on this finding. By forming a crack in the thickness direction in a coin-type negative electrode molded body, the division of the negative electrode molded body is positively induced. Control.

本発明は、リチウムの吸蔵および放出が可能な負極活物質を含む負極成型体を含み、負極成型体は、２つの平面部と側面部とを有するコイン型であり、かつ厚さ方向に亀裂を有する、コイン型リチウム二次電池用負極に関する。   The present invention includes a molded negative electrode including a negative electrode active material capable of occluding and releasing lithium, and the molded negative electrode is a coin type having two flat portions and side portions, and has cracks in the thickness direction. The present invention relates to a negative electrode for a coin-type lithium secondary battery.

本発明は、また、前記２つの平面部の少なくとも一方が凹部を有し、前記亀裂が、前記凹部を起点とする亀裂であるコイン型リチウム二次電池用負極に関する。
本発明は、更に、前記２つの平面部がそれぞれ凹部を有し、前記亀裂が前記凹部を起点とする亀裂であり、一方の平面部が有する凹部と、他方の平面部が有する凹部とが、少なくとも部分的に対向しているコイン型リチウム二次電池用負極に関する。 The present invention also relates to a negative electrode for a coin-type lithium secondary battery, in which at least one of the two flat portions has a recess, and the crack is a crack starting from the recess.
In the present invention, the two plane portions each have a recess, and the crack is a crack starting from the recess, and the recess that one plane portion has and the recess that the other plane portion has include: The present invention relates to a negative electrode for a coin-type lithium secondary battery that is at least partially opposed.

本発明は、また、正極と、正極を収容する正極缶と、負極と、負極を収容する負極缶、正極と負極との間に介在するセパレータとを含み、正極は、リチウムの吸蔵および放出が可能な正極活物質を含む正極成型体を含み、負極は、リチウムの吸蔵および放出が可能な負極活物質を含む負極成型体を含み、負極成型体は、２つの平面部と側面部とを有するコイン型であり、かつ厚さ方向に亀裂を有し、２つの平面部の少なくとも一方が凹部を有し、亀裂が凹部を起点とする亀裂である、コイン型リチウム二次電池に関する。   The present invention also includes a positive electrode, a positive electrode can containing the positive electrode, a negative electrode, a negative electrode can containing the negative electrode, and a separator interposed between the positive electrode and the negative electrode. The negative electrode includes a negative electrode molded body including a negative electrode active material capable of occluding and releasing lithium, and the negative electrode molded body includes two flat portions and a side surface portion. The present invention relates to a coin-type lithium secondary battery that is a coin type, has a crack in the thickness direction, has at least one of two flat portions with a recess, and the crack is a crack starting from the recess.

本発明は、また、正極と、正極を収容する正極缶と、負極と、負極を収容する負極缶、正極と負極との間に介在するセパレータとを含み、正極は、リチウムの吸蔵および放出が可能な正極活物質を含む正極成型体を含み、負極は、リチウムの吸蔵および放出が可能な負極活物質を含む負極成型体を含み、負極成型体は、２つの平面部と側面部とを有するコイン型であり、かつ厚さ方向に亀裂を有し、負極缶は、負極成型体と対向する面に凸部を有し、亀裂が、凸部と負極成型体との接触部を起点とする亀裂である、コイン型リチウム二次電池に関する。   The present invention also includes a positive electrode, a positive electrode can containing the positive electrode, a negative electrode, a negative electrode can containing the negative electrode, and a separator interposed between the positive electrode and the negative electrode. The negative electrode includes a negative electrode molded body including a negative electrode active material capable of occluding and releasing lithium, and the negative electrode molded body includes two flat portions and a side surface portion. It is a coin type and has a crack in the thickness direction. The negative electrode can has a convex portion on the surface facing the negative electrode molded body, and the crack starts from the contact portion between the convex portion and the negative electrode molded body. The present invention relates to a coin-type lithium secondary battery that is a crack.

本発明のコイン型リチウム二次電池において、前記凹部は、線状、円状、放射状、格子状、多角形状およびハニカム状よりなる群から選択される少なくとも１つのパターンで形成されていることが好ましい。また、前記凸部は、線状、円状、放射状、格子状、多角形状およびハニカム状よりなる群から選択される少なくとも１つのパターンで形成されていることが好ましい。   In the coin-type lithium secondary battery of the present invention, the recess is preferably formed with at least one pattern selected from the group consisting of a linear shape, a circular shape, a radial shape, a lattice shape, a polygonal shape, and a honeycomb shape. . Moreover, it is preferable that the said convex part is formed with the at least 1 pattern selected from the group which consists of linear form, circular form, radial form, lattice form, polygonal shape, and honeycomb form.

負極活物質は、遷移金属とＳｉとの合金、Ｓｉ、ＳｉＯx（０＜ｘ＜２）、ＳｎおよびＳｎＯx（０＜ｘ≦２）よりなる群から選択される少なくとも１種を含むことが好ましい。
負極活物質の結晶子サイズは、２０ｎｍ以下が好適である。 The negative electrode active material may include at least one selected from the group consisting of an alloy of a transition metal and Si, Si, SiO x (0 <x <2), Sn, and SnO x (0 <x ≦ 2). preferable.
The crystallite size of the negative electrode active material is preferably 20 nm or less.

本発明は、（i）リチウムの吸蔵および放出が可能な負極活物質を含む負極合剤を調製し、（ii）負極合剤を加圧成型して、２つの平面部と側面部とを有するコイン型の負極成型体を作製し、（iii）負極成型体の厚さ方向に亀裂を形成する工程、を有するコイン型リチウム二次電池用負極の製造方法に関する。   The present invention prepares (i) a negative electrode mixture containing a negative electrode active material capable of occluding and releasing lithium, and (ii) pressure-molding the negative electrode mixture to have two plane parts and a side part. The present invention relates to a method for producing a negative electrode for a coin-type lithium secondary battery, which includes a step of producing a coin-type negative electrode molded body and (iii) forming a crack in the thickness direction of the negative electrode molded body.

負極成型体を作製する工程（ii）は、前記２つの平面部の少なくとも一方に凹部を形成する工程を含むことができる。   The step (ii) of producing the molded negative electrode can include a step of forming a recess in at least one of the two flat portions.

亀裂を形成する工程（iii）は、例えば、以下の工程を含むことができる。
（ａ）負極成型体と対向する凸部を有する面を有する負極缶を供給し、負極成型体を、凸部を有する面に圧着する工程。
（ｂ）凸部を有する治具で支持した負極成型体に、リチウム金属を圧着する工程。
（ｃ）凹部を有する治具で支持した負極成型体に、リチウム金属を圧着する工程。
（ｄ）負極成型体と対向するリチウム金属を貼り付けた面を有する負極缶を供給し、凸部を有する治具で、前記負極成型体を押圧して、前記リチウム金属に前記負極成型体を圧着する工程。
（ｅ）負極成型体と対向するリチウム金属を貼り付けた面を有する負極缶を供給し、凹部を有する治具で、前記負極成型体を押圧して、前記リチウム金属に前記負極成型体を圧着する工程。 The step (iii) of forming a crack can include, for example, the following steps.
(A) The process of supplying the negative electrode can which has a surface which has a convex part facing a negative electrode molded object, and crimping | bonding a negative electrode molded object to the surface which has a convex part.
(B) A step of pressure bonding lithium metal to a molded negative electrode supported by a jig having a convex portion.
(C) A step of pressure-bonding lithium metal to a molded negative electrode supported by a jig having a recess.
(D) Supplying a negative electrode can having a surface to which a lithium metal facing the negative electrode molded body is attached, pressing the negative electrode molded body with a jig having a convex portion, and placing the negative electrode molded body on the lithium metal The process of crimping.
(E) Supplying a negative electrode can having a surface to which a lithium metal facing the negative electrode molded body is attached, pressing the negative electrode molded body with a jig having a recess, and crimping the negative electrode molded body to the lithium metal Process.

本発明の負極は、体積変化に対する追従性が向上し、負極構造の保持と集電経路の確保が容易である。よって、容量劣化が小さく（サイクル特性に優れ）、かつ高容量なコイン型リチウム二次電池を提供することができる。本発明では、高容量の材料を活物質に利用することができるので、従来の炭素材料を用いたリチウム二次電池に比べ、大幅な高容量化が可能である。また、本発明のリチウム二次電池は、従来のＡｌ板を用いたリチウム二次電池に比べ、大幅な長寿命化を図ることができる。   The negative electrode of the present invention has improved followability to volume change, and it is easy to maintain the negative electrode structure and secure a current collection path. Therefore, it is possible to provide a coin-type lithium secondary battery with small capacity deterioration (excellent in cycle characteristics) and high capacity. In the present invention, since a high-capacity material can be used as the active material, the capacity can be significantly increased as compared with a lithium secondary battery using a conventional carbon material. In addition, the lithium secondary battery of the present invention can have a significantly longer life than a conventional lithium secondary battery using an Al plate.

本発明のコイン型リチウム二次電池用負極は、リチウムの吸蔵および放出が可能な負極活物質を含む負極成型体を含む。負極成型体は、合剤の成型体、負極活物質の板材などを含む。ここで、合剤とは、負極活物質を必須成分として含む混合物である。合剤は、任意成分として、導電剤、結着剤などを含むことができる。   The negative electrode for coin-type lithium secondary batteries of the present invention includes a molded negative electrode containing a negative electrode active material capable of occluding and releasing lithium. The negative electrode molding includes a mixture molding, a negative electrode active material plate, and the like. Here, the mixture is a mixture containing a negative electrode active material as an essential component. The mixture can contain a conductive agent, a binder and the like as optional components.

負極成型体は、２つの平面部と側面部とを有するコイン型であり、かつ厚さ方向に亀裂を有する。ここで、厚さ方向の亀裂とは、一方の平面部から他方の平面部に至る亀裂を言う。厚さ方向の亀裂は、成型体の全体に均一に形成されていることが好ましい。負極成型体が厚さ方向の亀裂を有することで、負極の体積変化に対する追従性が向上し、負極構造の保持と集電経路の確保が容易となる。   The molded negative electrode is a coin type having two flat portions and side portions, and has a crack in the thickness direction. Here, the crack in the thickness direction refers to a crack extending from one plane portion to the other plane portion. The cracks in the thickness direction are preferably formed uniformly throughout the molded body. When the molded negative electrode has a crack in the thickness direction, the followability to the volume change of the negative electrode is improved, and the negative electrode structure can be easily held and the current collecting path can be easily secured.

負極成型体は、亀裂により、５〜１００個の区分に分割されることが好ましい。また、区分の１つあたりの平均的な大きさは、元の成型体の１体積％〜３０体積％であることが好ましい。１つの区分の大きさが大きすぎると、分割後の成型体が充放電サイクル中にさらに細分化して、厚さ方向の集電経路の一部が断絶され、分割の効果が不十分となる場合がある。一方、１つの区分の大きさが小さすぎると、負極成型体が細く分割され、厚さ方向の集電経路が断絶されやすくなる場合がある。   The molded negative electrode is preferably divided into 5 to 100 sections due to cracks. Moreover, it is preferable that the average magnitude | size per division is 1 volume%-30 volume% of the original molded object. If the size of one section is too large, the molded product after splitting will be further subdivided during the charge / discharge cycle, and part of the current collection path in the thickness direction will be cut off, resulting in insufficient splitting effect There is. On the other hand, if the size of one section is too small, the molded negative electrode may be finely divided and the current collecting path in the thickness direction may be easily cut off.

厚さ方向の亀裂は、例えば、負極成型体の少なくとも一方の平面部に凹部を形成することにより、以降に成型体に印加される応力によって凹部を起点として生成する。厚さ方向の亀裂は、電池缶内で、または電池缶外で生成させることができる。例えば、凹部を有する成型体を電池缶内に収容し、電池を完成させる。その後、完成した電池を充電または放電させると、負極活物質の膨張または収縮により、成型体に応力が印加される。その結果、電池缶内で、凹部を起点として亀裂が生成する。   The crack in the thickness direction is generated, for example, by forming a recess in at least one flat portion of the negative electrode molded body, and starting from the recess due to stress applied to the molded body. The crack in the thickness direction can be generated in the battery can or outside the battery can. For example, a molded body having a recess is accommodated in a battery can to complete the battery. Thereafter, when the completed battery is charged or discharged, stress is applied to the molded body due to expansion or contraction of the negative electrode active material. As a result, cracks are generated in the battery can starting from the recesses.

負極成型体の２つの平面部がそれぞれ凹部を有する場合、一方の平面部が有する凹部と、他方の平面部が有する凹部とが、少なくとも部分的に対向していることが好ましい。例えば、一方の平面部が有する凹部と、他方の平面部が有する凹部とが、成型体の平面部と平行で成型体の中心を通る平面に対して対称な形状を有することが好ましい。これにより、亀裂の方向と、成型体の厚さ方向とが、ほぼ平行となり、亀裂によって分割された各区分においては、厚さ方向の集電経路の連続性が保持される。２つの平面部の凹部が互いに対向していない場合、成型体の厚さ方向に対して傾斜した亀裂が生成する。この場合、各区分の厚さ方向の連続性が部分的に失われる。   When the two flat portions of the molded negative electrode each have a concave portion, it is preferable that the concave portion of one flat portion and the concave portion of the other flat portion are at least partially facing each other. For example, it is preferable that the concave portion included in one flat portion and the concave portion included in the other flat portion have a symmetrical shape with respect to a plane that is parallel to the flat portion of the molded body and passes through the center of the molded body. Thereby, the direction of a crack and the thickness direction of a molded object become substantially parallel, and the continuity of the current collection path | route of the thickness direction is maintained in each division divided | segmented by the crack. When the concave portions of the two flat portions do not face each other, a crack that is inclined with respect to the thickness direction of the molded body is generated. In this case, the continuity in the thickness direction of each section is partially lost.

成型体の厚さ方向に亀裂を形成するために、負極缶の成型体と対向する（接する）面に、凸部を設けてもよい。負極成型体に凹部を形成すると、負極成型体が脆くなりやすい。一方、負極缶の成型体と対向する面に凸部を設ける場合には、負極成型体に凹部を形成しなくても、厚さ方向の亀裂を効率よく生成させることができる。よって、負極成型体の強度低下を懸念することなく、本発明の目的を達成することができる。この場合、亀裂は、凸部と負極成型体との接触部を起点として形成される。   In order to form a crack in the thickness direction of the molded body, a convex portion may be provided on the surface facing (in contact with) the molded body of the negative electrode can. If the concave portion is formed in the molded negative electrode, the molded negative electrode tends to be brittle. On the other hand, when providing a convex part in the surface facing the molded object of a negative electrode can, the crack of a thickness direction can be produced | generated efficiently, without forming a recessed part in a negative electrode molded object. Therefore, the object of the present invention can be achieved without worrying about a decrease in strength of the molded negative electrode. In this case, the crack is formed starting from the contact portion between the convex portion and the negative electrode molded body.

成型体の平面部が有する凹部は、線状、円状、放射状、格子状、多角形状およびハニカム状よりなる群から選択される少なくとも１つのパターンで形成されていることが好ましい。また、負極缶の成型体と対向する面が有する凸部は、線状、円状、放射状、格子状、多角形状およびハニカム状よりなる群から選択される少なくとも１つのパターンで形成されていることが好ましい。多角形には、例えば三角形、四角形、六角形などが含まれるが、特に限定されない。線状とは、例えばストライプ状を含み、円状とは、例えば同心円状を含む。凹部は溝状（groove）であり、凸部はリブ状（rib）であることが好ましい。   The concave portion of the planar portion of the molded body is preferably formed in at least one pattern selected from the group consisting of a linear shape, a circular shape, a radial shape, a lattice shape, a polygonal shape, and a honeycomb shape. Further, the convex part of the surface facing the molded body of the negative electrode can is formed with at least one pattern selected from the group consisting of linear, circular, radial, grid, polygonal and honeycomb. Is preferred. Examples of the polygon include, but are not limited to, a triangle, a quadrangle, and a hexagon. The linear shape includes, for example, a stripe shape, and the circular shape includes, for example, a concentric circle shape. It is preferable that the concave portion has a groove shape and the convex portion has a rib shape.

なかでも、パターンが多角形状である場合、パターンは網目状であることが好ましい。特に最密に配置された三角形状、正方形状（格子状）または正六角形状（ハニカム状）のパターンの凹部または凸部が好ましい。最密に配置された三角形状の凹部または凸部は、角周辺に亀裂が入りやすい点で有利である。格子状およびハニカム状の凹部または凸部は、亀裂により分割された区分の形状維持が最も良好である点で有利である。格子状およびハニカム状の凹部または凸部によれば、成型体が亀裂で分割される際に、あまりに細か過ぎる区分が生成しにくいと考えられる。   Especially, when a pattern is polygonal, it is preferable that a pattern is mesh shape. In particular, a concave portion or a convex portion of a triangular shape, a square shape (lattice shape) or a regular hexagonal shape (honeycomb shape) arranged in a close packing is preferable. Closely arranged triangular concave or convex portions are advantageous in that they easily crack around the corners. The lattice-shaped and honeycomb-shaped concave portions or convex portions are advantageous in that the shape of the section divided by the crack is best maintained. According to the lattice-shaped and honeycomb-shaped concave portions or convex portions, it is considered that when the molded body is divided by cracks, a too fine section is hardly generated.

凹部により、負極成型体の平面部は、５〜１００個の区分に分割されることが好ましい。また、区分の１つあたりの平均的な面積は、元の平面部の面積の１％〜３０％であることが好ましい。
同様に、凸部により、負極缶の成型体との対向面は、５〜１００個の区分に分割されることが好ましい。また、区分の１つあたりの平均的な面積は、元の対向面の面積の１％〜３０％であることが好ましい。 The flat portion of the molded negative electrode is preferably divided into 5 to 100 sections by the recess. Moreover, it is preferable that the average area per division is 1% to 30% of the area of the original plane portion.
Similarly, it is preferable that the surface facing the molded body of the negative electrode can is divided into 5 to 100 sections by the convex portion. Moreover, it is preferable that the average area per division is 1% to 30% of the area of the original facing surface.

本発明のリチウム二次電池用負極は、例えば、以下の方法で作製することができる。
工程（i）
リチウムの吸蔵および放出が可能な負極活物質を含む負極合剤を調製する。負極合剤には、例えば、負極活物質と、導電剤と、結着剤とを含む混合物を用いる。導電剤には、例えばカーボンブラック、炭素繊維などが用いられる。結着剤には、例えばフッ素樹脂、ポリアクリル酸、ポリアクリレート、カルボキシルメチルセルロース、スチレン-ブタジエンゴム重合体などが用いられる。 The negative electrode for a lithium secondary battery of the present invention can be produced, for example, by the following method.
Process (i)
A negative electrode mixture containing a negative electrode active material capable of inserting and extracting lithium is prepared. For the negative electrode mixture, for example, a mixture containing a negative electrode active material, a conductive agent, and a binder is used. For example, carbon black or carbon fiber is used as the conductive agent. As the binder, for example, fluororesin, polyacrylic acid, polyacrylate, carboxymethyl cellulose, styrene-butadiene rubber polymer and the like are used.

工程（ii）
負極合剤を加圧成型して、２つの平面部と側面部とを有するコイン型の負極成型体（ペレット）を作製する。このとき同時に、前記２つの平面部の少なくとも一方に所定の凹部を形成してもよい。すなわち、負極合剤を加圧成型してコイン型の負極成型体を作製する工程と、凹部の形成とは、同時に行うことができる。 Step (ii)
The negative electrode mixture is pressure-molded to produce a coin-shaped negative electrode molded body (pellet) having two flat portions and side portions. At the same time, a predetermined recess may be formed in at least one of the two flat portions. That is, the step of producing a coin-type negative electrode molding by pressure molding of the negative electrode mixture and the formation of the recess can be performed simultaneously.

工程（iii）
負極成型体の厚さ方向に亀裂を形成する。厚さ方向の亀裂は、負極成型体の少なくとも一方の平面部に凹部を形成する場合には、充放電時の負極活物質の体積変化により生成させることが好ましい。負極成型体に凹部を形成しない場合には、電池構成時に亀裂を形成してもよい。また、負極成型体を予めカッターなどで分割する工程も、亀裂を形成する工程に含まれる。 Step (iii)
Cracks are formed in the thickness direction of the molded negative electrode. The crack in the thickness direction is preferably generated by a change in the volume of the negative electrode active material during charge / discharge when a recess is formed in at least one flat portion of the molded negative electrode. In the case where no concave portion is formed in the molded negative electrode, a crack may be formed during the battery configuration. Moreover, the process of dividing | segmenting a negative electrode molded object previously with a cutter etc. is also contained in the process of forming a crack.

亀裂を形成する工程（iii）を以下のように行う場合、平面部に凹部を有さない負極成型体を用いることができる。ただし、平面部に凹部を有する負極成型体を用いてもよい。
工程（ａ）
負極成型体と対向する凸部を有する面を有する負極缶を準備する。そして、負極成型体を、負極缶の凸部を有する面に圧着する。ただし、負極成型体に凹部が形成されるのは、電池構成時（すなわち負極成型体を負極缶の凸部を有する面に圧着しているとき）でもよく、完成後の電池の充放電中でもよい。また、必ずしも負極成型体に凹部が形成される必要はない。負極缶の凸部を起点に、負極成型体に厚さ方向の亀裂が発生すれば本発明の目的は達成される。なお、電池構成前に亀裂が形成されると、負極成型体の一部が脱落しやすいため、負極成型体の厚さ方向に亀裂が形成されるのは、電池構成時以降が望ましい。 When the step (iii) of forming a crack is performed as follows, a molded negative electrode having no concave portion in the plane portion can be used. However, you may use the negative electrode molding which has a recessed part in a plane part.
Step (a)
A negative electrode can having a surface having a convex portion facing the negative electrode molded body is prepared. And a negative electrode molded object is crimped | bonded to the surface which has a convex part of a negative electrode can. However, the concave portion may be formed in the molded negative electrode during battery construction (that is, when the molded negative electrode is pressure-bonded to the surface having the convex portion of the negative electrode can) or during charge / discharge of the battery after completion. . Further, it is not always necessary to form a recess in the negative electrode molded body. The object of the present invention is achieved if a crack in the thickness direction occurs in the molded negative electrode starting from the convex portion of the negative electrode can. In addition, if a crack is formed before the battery configuration, a part of the molded negative electrode is likely to drop off. Therefore, it is desirable that the crack is formed in the thickness direction of the molded negative electrode after the battery configuration.

工程（ｂ）
凸部を有する治具で支持した負極成型体に、リチウム金属を圧着する。負極成型体にリチウム金属を圧着する際には、リチウム金属を押圧する治具と、負極成型体を支持する治具とを用いる。負極成型体を支持する治具の表面には凸部を形成する。これにより、負極成型体とリチウム箔との圧着時に、凸部を起点として、負極成型体に厚さ方向の亀裂が生じる。 Step (b)
Lithium metal is pressure-bonded to a molded negative electrode supported by a jig having a convex portion. When pressure-bonding lithium metal to the molded negative electrode, a jig for pressing the lithium metal and a jig for supporting the molded negative electrode are used. A convex portion is formed on the surface of the jig that supports the molded negative electrode. Thereby, at the time of pressure bonding of the negative electrode molded body and the lithium foil, a crack in the thickness direction occurs in the negative electrode molded body starting from the convex portion.

工程（ｃ）
凹部を有する治具で支持した負極成型体に、リチウム金属を圧着する。負極成型体にリチウム金属を圧着する際には、リチウム金属を押圧する治具と、負極成型体を支持する治具とを用いる。負極成型体を支持する治具の表面には凹部を形成する。これにより、負極成型体とリチウム箔との圧着時に、凹部を起点として、負極成型体に厚さ方向の亀裂が生じる。 Step (c)
Lithium metal is pressure-bonded to a molded negative electrode supported by a jig having a recess. When pressure-bonding lithium metal to the molded negative electrode, a jig for pressing the lithium metal and a jig for supporting the molded negative electrode are used. A recess is formed on the surface of the jig that supports the molded negative electrode. Thereby, at the time of pressure bonding of the negative electrode molded body and the lithium foil, a crack in the thickness direction is generated in the negative electrode molded body starting from the recess.

工程（ｄ）
凸部を有する治具で、負極成型体を押圧して、リチウム金属に圧着する。負極缶の負極成型体との対向面には、予めリチウム金属を圧着する。負極成型体にリチウム金属を圧着する際には、負極成型体を押圧する治具を用いる。負極成型体を押圧する治具１１の表面には、凸部を形成する。リチウム金属の上に負極成型体を載置し、凸部を有する治具で負極成型体を押圧して、リチウム金属を圧着する。その際、凸部を起点として、負極成型体に厚さ方向の亀裂が生じる。 Step (d)
The negative electrode molded body is pressed with a jig having a convex portion and pressed against lithium metal. Lithium metal is pressure-bonded in advance on the surface of the negative electrode can facing the negative electrode molded body. When the lithium metal is pressure bonded to the molded negative electrode, a jig for pressing the molded negative electrode is used. A convex portion is formed on the surface of the jig 11 that presses the negative electrode molded body. The negative electrode molded body is placed on the lithium metal, and the negative electrode molded body is pressed with a jig having a convex portion to crimp the lithium metal. At that time, a crack in the thickness direction occurs in the molded negative electrode starting from the convex portion.

工程（ｅ）
凹部を有する治具で、負極成型体を押圧して、リチウム金属に圧着する。負極缶の負極成型体との対向面には、予めリチウム金属を圧着する。負極成型体にリチウム金属を圧着する際には、負極成型体を押圧する治具を用いる。負極成型体を押圧する治具の表面には、凹部を形成する。リチウム金属の上に負極成型体を載置し、凹部を有する治具で負極成型体を押圧して、リチウム金属を圧着する。その際、凹部を起点として、負極成型体に厚さ方向の亀裂８が生じる。 Step (e)
The negative electrode molded body is pressed with a jig having a concave portion and pressed against lithium metal. Lithium metal is pressure-bonded in advance on the surface of the negative electrode can facing the negative electrode molded body. When the lithium metal is pressure bonded to the molded negative electrode, a jig for pressing the molded negative electrode is used. A recess is formed on the surface of the jig that presses the molded negative electrode. The negative electrode molded body is placed on the lithium metal, and the negative electrode molded body is pressed with a jig having a recess to press the lithium metal. At that time, a crack 8 in the thickness direction is generated in the molded negative electrode starting from the concave portion.

負極成型体の平面部もしくは冶具が有する凹部、または、負極缶もしくは冶具が有する凸部の間隔は、０．１ｍｍ〜３．０ｍｍが好ましく、０．２〜２．１ｍｍが更に好ましい。ここで、凹部または凸部の間隔とは、凹部または凸部がストライプ状や同心円状の場合には、隣接する凹部または凸部の最短距離であり、円状の場合には円の半径、多角形状の場合には多角形の高さである。凹部または凸部の間隔が、０．１ｍｍより小さくなると、亀裂で負極成型体が細く分割されすぎ、厚さ方向の集電経路が断絶されやすくなる場合がある。一方、間隔が３．０ｍｍより大きくなると、分割後の成型体が充放電サイクル中にさらに細分化して、厚さ方向の集電経路の一部が断絶され、分割の効果が不十分となる場合がある。なお、ここでの各数値は、厚さ約０．３ｍｍの負極成型体を想定している。   The distance between the flat part of the molded negative electrode or the concave part of the jig or the convex part of the negative electrode can or the jig is preferably 0.1 mm to 3.0 mm, and more preferably 0.2 to 2.1 mm. Here, the interval between recesses or projections is the shortest distance between adjacent recesses or projections when the recesses or projections are striped or concentric, and in the case of a circle, the radius of the circle, the polygon In the case of shape, it is the height of the polygon. If the interval between the concave portions or the convex portions is smaller than 0.1 mm, the negative electrode molded body is too thinly divided by cracks, and the current collecting path in the thickness direction may be easily cut off. On the other hand, when the interval is larger than 3.0 mm, the divided molded body is further subdivided during the charge / discharge cycle, and part of the current collecting path in the thickness direction is cut off, and the effect of the division becomes insufficient There is. In addition, each numerical value here assumes the negative electrode molded object of thickness about 0.3mm.

負極成型体の平面部もしくは冶具が有する凹部、または、負極缶もしくは冶具が有する凸部の間隔の最適値は、負極成型体の厚さと、亀裂による分割後の各区分の幅とのアスペクト比により左右される。負極成型体の厚さをＴとするとき、凹部または凸部の間隔は、０．７Ｔ〜７Ｔが最適である。例えば、負極成型体の厚さが０．２ｍｍであれば、凹部または凸部の間隔の最適値は０．１４〜１．４ｍｍとなる。   The optimum value of the gap between the flat part of the molded negative electrode or the concave part of the jig, or the convex part of the negative electrode can or the jig depends on the aspect ratio between the thickness of the molded negative electrode and the width of each section after division by cracks. It depends. When the thickness of the molded negative electrode is T, 0.7T to 7T is optimal for the interval between the concave portions or the convex portions. For example, when the thickness of the molded negative electrode is 0.2 mm, the optimum value of the interval between the concave portions or the convex portions is 0.14 to 1.4 mm.

負極成型体の平面部もしくは治具が有する凹部の深さ、または、負極缶もしくは冶具が有する凸部の高さは、０．０１ｍｍ〜０．１ｍｍが好ましく、０．０３〜０．０６ｍｍが更に好ましい。凹部の深さまたは凸部の高さが０．０１ｍｍより小さいと、亀裂の入り方にばらつきが生じ、負極成型体が均一に分割されにくい場合がある。また、凹部の深さまたは凸部の高さが０．１ｍｍより大きいと、負極成型体の強度が低下するため、電池構成時において、その取り扱いが困難になる場合がある。なお、ここでの各数値は、厚さ約０．３ｍｍの負極成型体を想定している。   The depth of the concave part of the flat part of the negative electrode molded body or the jig or the height of the convex part of the negative electrode can or the jig is preferably 0.01 mm to 0.1 mm, more preferably 0.03 to 0.06 mm. preferable. When the depth of the concave portion or the height of the convex portion is smaller than 0.01 mm, there are variations in how cracks are formed, and the negative electrode molded body may be difficult to be uniformly divided. In addition, when the depth of the concave portion or the height of the convex portion is larger than 0.1 mm, the strength of the molded negative electrode is lowered, so that it may be difficult to handle at the time of battery configuration. In addition, each numerical value here assumes the negative electrode molded object of thickness about 0.3mm.

凹部の深さまたは凸部の高さの最適値は、負極成型体の厚さに左右される。負極成型体の厚さをＴとするとき、凹部の深さまたは凸部の高さは、０．１Ｔ〜０．２Ｔが最適である。例えば、負極成型体の厚さが０．２ｍｍであれば、凹部の深さまたは凸部の高さの最適値は０．０２〜０．０４ｍｍが最適となる。   The optimum value of the depth of the concave portion or the height of the convex portion depends on the thickness of the negative electrode molded body. When the thickness of the molded negative electrode is T, the depth of the concave portion or the height of the convex portion is optimally 0.1T to 0.2T. For example, if the thickness of the molded negative electrode is 0.2 mm, the optimum value of the depth of the concave portion or the height of the convex portion is 0.02 to 0.04 mm.

支持治具に凹部を形成する場合の深さは、より深い方が好ましいが、０．０１ｍｍ以上であればよく、０．０３ｍｍ以上が好ましい。支持治具の凹部の深さが０．０１ｍｍより小さいと、亀裂の入り方にばらつきが生じ、負極成型体が均一に分割されにくい。なお、ここでの各数値は、厚さ約０．３ｍｍの負極成型体を想定している。凹部の深さの最適値は、負極成型体の厚さに左右される。負極成型体の厚さをＴとするとき、凹部の深さは、０．１Ｔ以上が最適である。例えば、負極成型体の厚さが０．２ｍｍであれば、凹部の深さまたは凸部の高さの最適値は０．０２ｍｍ以上が最適となる。   The depth when the recess is formed in the support jig is preferably deeper, but may be 0.01 mm or more, and preferably 0.03 mm or more. If the depth of the concave portion of the support jig is smaller than 0.01 mm, the cracks will vary in how they are formed, and the molded negative electrode is difficult to be uniformly divided. In addition, each numerical value here assumes the negative electrode molded object of thickness about 0.3mm. The optimum value of the depth of the recess depends on the thickness of the molded negative electrode. When the thickness of the molded negative electrode is T, the depth of the recess is optimally 0.1T or more. For example, when the thickness of the molded negative electrode is 0.2 mm, the optimum value of the depth of the concave portion or the height of the convex portion is 0.02 mm or more.

負極成型体の平面部もしくは治具が有する凹部または負極缶もしくは治具が有する凸部の幅（最大幅）は、より小さい方が好ましいが、凹部の深さまたは凸部の高さをＨとするとき、１．５Ｈ以下が好ましく、１．０Ｈ以下が更に好ましい。幅が１．５Ｈより大きくなると、亀裂を深さ方向に制御することが困難となり、厚さ方向の集電経路が断絶しやすくなる場合がある。   The width (maximum width) of the concave part of the flat part of the negative electrode molded body or the jig or the convex part of the negative electrode can or the jig is preferably smaller, but the depth of the concave part or the height of the convex part is H. When it does, 1.5H or less is preferable and 1.0H or less is still more preferable. When the width is larger than 1.5H, it becomes difficult to control the crack in the depth direction, and the current collecting path in the thickness direction may be easily disconnected.

上記のように、負極成型体の平面部に凹部を設け、または、負極缶もしくは冶具の成型体との対向面に凸部もしくは凹部を設けることにより、その凹部または凸部を起点に負極成型体の分割が誘起される。一旦分割された後では、負極成型体の形状維持が良好となり、その厚さ方向の集電経路の断絶が緩和される。このような効果が得られる理由は明らかでないが、負極成型体の分割により、活物質の膨張収縮による応力の蓄積が緩和されることと関連すると考えられる。   As described above, a concave portion is provided in the flat portion of the negative electrode molded body, or a convex portion or a concave portion is provided on the surface facing the negative electrode can or the molded body of the jig, whereby the negative electrode molded body starts from the concave portion or the convex portion. Is induced. Once divided, the shape of the negative electrode molded body is maintained well, and the disconnection of the current collecting path in the thickness direction is alleviated. The reason why such an effect is obtained is not clear, but is considered to be related to the fact that the accumulation of stress due to the expansion and contraction of the active material is alleviated by the division of the molded negative electrode.

負極活物質には、Ｓｉ系材料またはＳｎ系材料を用いることが好ましい。例えば、遷移金属とＳｉとの合金、Ｓｉ、ＳｉＯx（０＜ｘ＜２）、ＳｎおよびＳｎＯx（０＜ｘ≦２）よりなる群から選択される少なくとも１種を用いることが好ましい。遷移金属とＳｉとの合金の場合、遷移金属としては、Ｃｒ、Ｍｎ、Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ、Ｍｏ、Ａｇ、Ｔｉ、Ｚｒ、ＨｆおよびＷなどが挙げられる。これらのうちではＴｉが好ましい。Ｓｉ−Ｔｉ合金（例えばＴｉＳｉ2）は電子伝導度が高い点で有利である。なお、遷移金属とＳｉとの合金は、リチウムに対して不活性な金属間化合物相とＳｉ相とを含む。このような２相以上を含む合金粒子は、高容量化と体積膨張の抑制とを両立させる観点から好ましい。 As the negative electrode active material, it is preferable to use a Si-based material or a Sn-based material. For example, it is preferable to use at least one selected from the group consisting of an alloy of a transition metal and Si, Si, SiO x (0 <x <2), Sn and SnO x (0 <x ≦ 2). In the case of an alloy of a transition metal and Si, examples of the transition metal include Cr, Mn, Fe, Co, Ni, Cu, Mo, Ag, Ti, Zr, Hf, and W. Of these, Ti is preferred. Si—Ti alloys (eg, TiSi 2 ) are advantageous in that they have high electron conductivity. The alloy of transition metal and Si contains an intermetallic compound phase and an Si phase that are inert to lithium. Such alloy particles containing two or more phases are preferable from the viewpoint of achieving both high capacity and suppression of volume expansion.

負極活物質は、特に限定されないが、非晶質状態、微結晶状態、または、非晶質領域と微結晶領域との混合状態であることが望ましく、非晶質領域と微結晶領域との混合状態が最も望ましい。非晶質状態とは、ＣｕＫα線を用いたＸ線回折像（回折パターン）が結晶面に帰属される明確なピークを有さず、ブロードな回折像しか有さない状態である。微結晶状態とは、結晶子サイズが２０ｎｍ以下の状態である。これらの状態は、透過電子顕微鏡（ＴＥＭ）により直接観察できる。また、Ｘ線回折分析で得られるピークの半価幅から、Ｓｃｈｅｒｒｅｒの式を用いて求めることもできる。結晶子サイズが２０ｎｍより大きくなると、充放電時の体積変化に活物質粒子の機械的強度が追従できず、粒子割れなどが起こり、集電状態が低下する場合がある。   The negative electrode active material is not particularly limited, but is preferably in an amorphous state, a microcrystalline state, or a mixed state of an amorphous region and a microcrystalline region. The state is most desirable. The amorphous state is a state in which an X-ray diffraction image (diffraction pattern) using CuKα rays does not have a clear peak attributed to a crystal plane and has only a broad diffraction image. The microcrystalline state is a state where the crystallite size is 20 nm or less. These states can be directly observed with a transmission electron microscope (TEM). It can also be determined from the half width of the peak obtained by X-ray diffraction analysis using the Scherrer equation. When the crystallite size is larger than 20 nm, the mechanical strength of the active material particles cannot follow the volume change at the time of charge / discharge, particle breakage or the like may occur, and the current collection state may be lowered.

非晶質状態、微結晶状態、または、非晶質領域と微結晶領域との混合状態の負極活物質を得る方法としては、機械的粉砕混合方法（メカニカルアロイング法）が挙げられる。メカニカルアロイング法では、ボールミル、振動ミル、遊星ボールミルなどの装置を用いる。与える重力加速度の大きさと、大型化の容易さの観点から、振動ミルが最も好ましい。   Examples of a method for obtaining a negative electrode active material in an amorphous state, a microcrystalline state, or a mixed state of an amorphous region and a microcrystalline region include a mechanical grinding and mixing method (mechanical alloying method). In the mechanical alloying method, devices such as a ball mill, a vibration mill, and a planetary ball mill are used. The vibration mill is most preferable from the viewpoint of the gravitational acceleration to be applied and the ease of enlargement.

負極活物質の比表面積は、特に限定されないが、０．５〜２０ｍ2／ｇの範囲内が好ましい。比表面積が０．５ｍ2／ｇ未満では、電解液との接触面積が減少して、充放電効率が低下する場合がある。比表面積が２０ｍ2／ｇを超えると、電解液との反応性が過剰となって、不可逆容量が増大する場合がある。 Although the specific surface area of a negative electrode active material is not specifically limited, The inside of the range of 0.5-20 m < 2 > / g is preferable. When the specific surface area is less than 0.5 m 2 / g, the contact area with the electrolytic solution may decrease, and the charge / discharge efficiency may decrease. When the specific surface area exceeds 20 m 2 / g, the reactivity with the electrolytic solution becomes excessive, and the irreversible capacity may increase.

負極活物質の平均粒径は、特に限定されないが、０．１〜１０μｍの範囲内が好ましい。平均粒径が０．１μｍ未満では、比表面積が大きくなり、電解液との反応性が過剰となって、不可逆容量が増大する場合がある。平均粒径が１０μｍを超えると、比表面積が小さくなり、電解液との接触面積が減少して、充放電効率が低下する場合がある。   Although the average particle diameter of a negative electrode active material is not specifically limited, The inside of the range of 0.1-10 micrometers is preferable. When the average particle size is less than 0.1 μm, the specific surface area becomes large, the reactivity with the electrolytic solution becomes excessive, and the irreversible capacity may increase. When the average particle diameter exceeds 10 μm, the specific surface area becomes small, the contact area with the electrolytic solution decreases, and the charge / discharge efficiency may decrease.

Ｓｉ系材料またはＳｎ系材料を用いる場合、負極活物質の表面にＳｉ酸化物またはＳｎ酸化物を含む被膜を形成させることが好ましい。被膜を形成させる方法としては、密閉容器内で負極活物質を攪拌しながら、徐々に容器内に酸素を導入する方法が挙げられる。その際、密閉容器を、水冷ジャケットなどの放熱機構で冷却し、活物質の温度上昇を抑制することにより、処理時間を短くすることができる。このような攪拌機能を有する密閉容器を具備する装置として、振動乾燥機、混練機などが挙げられる。   In the case of using a Si-based material or a Sn-based material, it is preferable to form a film containing Si oxide or Sn oxide on the surface of the negative electrode active material. Examples of the method for forming the coating include a method of gradually introducing oxygen into the container while stirring the negative electrode active material in the sealed container. At that time, the processing time can be shortened by cooling the sealed container with a heat dissipation mechanism such as a water cooling jacket to suppress the temperature rise of the active material. Examples of the apparatus having a closed container having such a stirring function include a vibration dryer and a kneader.

本発明のコイン型リチウム二次電池は、負極とそれを収容する負極缶の他に、正極と、正極を収容する正極缶と、正極と負極との間に介在するセパレータとを含む。また、コイン型リチウム二次電池は、一般にリチウムイオン伝導性の電解液を含む。正極は、リチウムの吸蔵および放出が可能な正極活物質を含む正極成型体を含む。正極（正極成型体）、正極缶、リチウムイオン伝導性の電解液には、従来のコイン型リチウム二次電池と同様のものを用いることができる。   The coin-type lithium secondary battery of the present invention includes a positive electrode, a positive electrode can containing the positive electrode, and a separator interposed between the positive electrode and the negative electrode, in addition to the negative electrode and the negative electrode can containing the negative electrode. Coin-type lithium secondary batteries generally contain a lithium ion conductive electrolyte. The positive electrode includes a molded positive electrode including a positive electrode active material capable of inserting and extracting lithium. As the positive electrode (positive electrode molded body), the positive electrode can, and the lithium ion conductive electrolyte, the same one as a conventional coin-type lithium secondary battery can be used.

以下、本発明を実施例に基づいて具体的に説明する。ただし、本発明の内容は、これらの実施例に限定されるものではない。
《実施例１》
図１に示すようなコイン型リチウム二次電池を作製した。
（i）正極活物質の合成
二酸化マンガンと水酸化リチウムとを、モル比で２：１の割合で混合した。この混合物を、空気中４００℃で１２時間焼成し、マンガン酸リチウムを得た。これを正極活物質とした。 Hereinafter, the present invention will be specifically described based on examples. However, the contents of the present invention are not limited to these examples.
Example 1
A coin-type lithium secondary battery as shown in FIG. 1 was produced.
(I) Synthesis of positive electrode active material Manganese dioxide and lithium hydroxide were mixed at a molar ratio of 2: 1. This mixture was calcined in the air at 400 ° C. for 12 hours to obtain lithium manganate. This was used as a positive electrode active material.

（ii）正極の作製
正極活物質であるマンガン酸リチウムと、導電剤であるアセチレンブラックと、結着剤であるポリテトラフルオロエチレンの水性ディスパージョンとを、固形分の重量比で８８：６：６の割合で混合し、正極合剤を得た。正極合剤を、直径４ｍｍ、厚さ１．０ｍｍのコイン型のペレットに成型した。得られたペレットを、２５０℃で１２時間乾燥し、正極成型体４とした。 (Ii) Production of positive electrode Lithium manganate, which is a positive electrode active material, acetylene black, which is a conductive agent, and an aqueous dispersion of polytetrafluoroethylene, which is a binder, are in a weight ratio of 88: 6: The mixture was mixed at a ratio of 6 to obtain a positive electrode mixture. The positive electrode mixture was molded into a coin-shaped pellet having a diameter of 4 mm and a thickness of 1.0 mm. The obtained pellets were dried at 250 ° C. for 12 hours to obtain a positive electrode molded body 4.

（iii）負極活物質の合成
負極活物質として、Ｓｉ−Ｔｉ合金を合成した。Ｓｉ粉末およびＴｉ粉末を、元素モル比が７４．５：２５．５となるように混合した。この混合物１．７ｋｇを、ステンレス鋼製の内容積６４Ｌの容器を具備する中央化工機（株）製の振動ボールミル装置（ＦＶ−２０型）に、直径１インチのステンレス鋼ボール３００ｋｇとともに投入した。アルゴンガスで容器内の空気を置換した後、振幅８ｍｍ、振動数１２００ｒｐｍで、６０時間のメカニカルアロイングを行い、Ｓｉ−Ｔｉ合金を得た。 (Iii) Synthesis of negative electrode active material A Si-Ti alloy was synthesized as a negative electrode active material. Si powder and Ti powder were mixed so that the element molar ratio was 74.5: 25.5. 1.7 kg of this mixture was put into a vibrating ball mill device (FV-20 type) manufactured by Chuo Kakoki Co., Ltd. equipped with a stainless steel container with an internal volume of 64 L together with 300 kg of stainless steel balls having a diameter of 1 inch. After substituting the air in the container with argon gas, mechanical alloying was performed for 60 hours at an amplitude of 8 mm and a vibration frequency of 1200 rpm to obtain a Si—Ti alloy.

ＸＲＤの観察結果より、Ｓｉ−Ｔｉ合金は、少なくともＳｉ相とＴｉＳｉ2相とを含み、Ｓｉ相は非晶質、ＴｉＳｉ2相は微結晶であることが判明した。ＸＲＤのピーク位置および半価幅と、Ｓｃｈｅｒｒｅｒの式とを用い、ＴｉＳｉ2相の結晶子サイズを計算したところ、１５ｎｍであった。Ｔｉ−Ｓｉ相とＳｉ相との重量比は、Ｔｉが全てＴｉＳｉ2を形成したと仮定すると、４：１であった。 From the observation results of XRD, it was found that the Si—Ti alloy contains at least a Si phase and a TiSi 2 phase, the Si phase is amorphous, and the TiSi 2 phase is microcrystalline. The crystallite size of the TiSi 2 phase was calculated using the XRD peak position and half width, and the Scherrer equation, and it was 15 nm. The weight ratio of the TiSi phase and Si phase, assuming Ti was formed all TiSi 2, 4: 1.

Ｓｉ−Ｔｉ合金を、アルゴン雰囲気を保ったまま、攪拌装置を具備する中央化工機（製）の振動乾燥機（ＶＵ３０型）の密閉容器に回収した。Ｓｉ−Ｔｉ合金を振動攪拌しながら、密閉容器内にアルゴンと酸素との混合ガスを１時間かけて断続的に導入した。その間、Ｓｉ−Ｔｉ合金の温度が１００℃を越えないように密閉容器を冷却した。こうしてＳｉ−Ｔｉ合金の表面に、Ｓｉ酸化物を含む被膜を形成した。その後、Ｓｉ−Ｔｉ合金を篩いにかけて６３μｍ以下の粒子に整粒した。これを負極活物質とした。   The Si—Ti alloy was recovered in a sealed container of a vibration dryer (VU30 type) of Chuo Kakoki Co., Ltd. (manufactured) equipped with a stirring device while maintaining an argon atmosphere. While the Si—Ti alloy was vibrated and stirred, a mixed gas of argon and oxygen was intermittently introduced into the sealed container over 1 hour. Meanwhile, the sealed container was cooled so that the temperature of the Si—Ti alloy did not exceed 100 ° C. Thus, a film containing Si oxide was formed on the surface of the Si—Ti alloy. Thereafter, the Si—Ti alloy was sieved to adjust the particle size to 63 μm or less. This was made into the negative electrode active material.

（iv）負極の作製
負極活物質であるＳｉ−Ｔｉ合金と、導電剤であるカーボンブラックと、結着剤であるポリアクリル酸とを、重量比で１００：２０：１０の割合で混合し、負極合剤を得た。金型で、負極合剤を、直径４ｍｍ、厚さ０．３ｍｍのコイン型のペレットに成型した。その際、予め一方の金型の表面に、幅および高さ０．０５ｍｍのリブ状の凸部を、正方形の一辺の長さが０．８ｍｍの格子状のパターンで設けた。これにより、負極成型体（ペレット）の作製と同時に、負極成型体の一方の平面部に幅および深さ０．０５ｍｍの凹部を、間隔０．８ｍｍの格子状のパターンで形成した。その後、ペレットを、２００℃で１２時間乾燥し、負極成型体６とした。 (Iv) Production of negative electrode Si—Ti alloy as a negative electrode active material, carbon black as a conductive agent, and polyacrylic acid as a binder are mixed in a weight ratio of 100: 20: 10, A negative electrode mixture was obtained. The negative electrode mixture was molded into coin-shaped pellets having a diameter of 4 mm and a thickness of 0.3 mm using a mold. At that time, rib-shaped convex portions having a width and a height of 0.05 mm were previously provided on the surface of one mold in a lattice-like pattern having a square side length of 0.8 mm. Thereby, simultaneously with the production of the molded negative electrode (pellet), concave portions having a width and a depth of 0.05 mm were formed in a lattice pattern with a spacing of 0.8 mm on one flat surface portion of the molded negative electrode. Thereafter, the pellet was dried at 200 ° C. for 12 hours to obtain a negative electrode molded body 6.

図２に示すように、負極成型体６の一方の平面部には、格子状の凹部７が形成されていた。凹部７により、負極成型体の平面部は、２１個に区分され、区分の１つあたりの平均的な面積は、元の平面部の面積の約５％であった。   As shown in FIG. 2, a lattice-shaped concave portion 7 was formed on one flat portion of the negative electrode molded body 6. The flat part of the molded negative electrode was divided into 21 parts by the concave part 7, and the average area per one part was about 5% of the area of the original flat part.

（v）電解液の調製
プロピレンカーボネート（ＰＣ）と、エチレンカーボネート（ＥＣ）と、ジメチルエーテル（ＤＭＥ）との体積比１：１：１の混合溶媒に、リチウム塩としてＬｉＮ（ＣＦ3ＳＯ2）2を１ｍｏｌ／Ｌの濃度で溶解し、リチウムイオン伝導性の電解液を得た。 (V) Preparation of electrolytic solution LiN (CF 3 SO 2 ) 2 as a lithium salt in a mixed solvent of propylene carbonate (PC), ethylene carbonate (EC), and dimethyl ether (DME) in a volume ratio of 1: 1: 1. Was dissolved at a concentration of 1 mol / L to obtain a lithium ion conductive electrolyte.

（vi）試験電池の作製
図１は、作製したコイン型リチウム二次電池の縦断面図である。本実施例では、直径６．８ｍｍ、厚さ２．１ｍｍの寸法を有する電池を作製した。図１において、正極缶１は正極端子を兼ねており、耐食性の優れたステンレス鋼からなる。負極缶２は負極端子を兼ねており、正極缶１と同じ材質のステンレス鋼からなる。ガスケット３は正極缶１と負極缶２を絶縁しており、ポリプロピレン製である。正極缶１とガスケット３との接面および負極缶２とガスケット３との接面にはピッチが塗布されている。正極成型体４と負極成型体６との間には、ポリプロピレン製の不織布からなるセパレータ５が配されている。 (Vi) Production of Test Battery FIG. 1 is a longitudinal sectional view of the produced coin-type lithium secondary battery. In this example, a battery having a diameter of 6.8 mm and a thickness of 2.1 mm was produced. In FIG. 1, the positive electrode can 1 also serves as a positive electrode terminal and is made of stainless steel having excellent corrosion resistance. The negative electrode can 2 also serves as a negative electrode terminal and is made of stainless steel made of the same material as the positive electrode can 1. The gasket 3 insulates the positive electrode can 1 and the negative electrode can 2 and is made of polypropylene. Pitch is applied to the contact surface between the positive electrode can 1 and the gasket 3 and the contact surface between the negative electrode can 2 and the gasket 3. A separator 5 made of a nonwoven fabric made of polypropylene is disposed between the positive electrode molded body 4 and the negative electrode molded body 6.

まず、正極缶１の中央に正極成型体４を載置し、その上にセパレータ５を配した。次に、セパレータ５の上から１５μＬの電解液を注液した。負極成型体６の凹部を有さない方の平坦部には、所定の治具を用いて、負極活物質をリチウムと合金化させるためのリチウム箔を圧着し、その面をセパレータ５と対向させた。負極成型体６の凹部を有する方の平面部は、負極缶２側（図１の上側）に配した。電解液の存在下では、負極活物質がリチウム箔から供給されるリチウムを電気化学的に吸蔵してリチウム合金を形成する。リチウムを吸蔵した負極成型体の見かけ体積（内部空隙を含む体積）は、リチウムを吸蔵する前の１．６倍に膨張した。
以上のようにして作製した試験電池を電池Ａ１ａとした。 First, the positive electrode molded body 4 was placed in the center of the positive electrode can 1, and the separator 5 was disposed thereon. Next, 15 μL of electrolyte solution was injected from above the separator 5. On the flat portion of the negative electrode molded body 6 that does not have a recess, a predetermined jig is used to press-bond a lithium foil for alloying the negative electrode active material with lithium, and the surface thereof faces the separator 5. It was. The flat portion having the concave portion of the negative electrode molded body 6 was disposed on the negative electrode can 2 side (the upper side in FIG. 1). In the presence of the electrolytic solution, the negative electrode active material electrochemically occludes lithium supplied from the lithium foil to form a lithium alloy. The apparent volume (volume including internal voids) of the molded negative electrode containing lithium was expanded 1.6 times before lithium was occluded.
The test battery produced as described above was designated as battery A1a.

図５に示すようなハニカム状の凹部を形成したこと以外、電池Ａ１ａと同様に、試験電池Ａ１ｂを作製した。凹部の深さと幅は、電池Ａ１ａと同じとした。正六角形の高さは０．８ｍｍとした。   A test battery A1b was produced in the same manner as the battery A1a, except that a honeycomb-shaped recess as shown in FIG. 5 was formed. The depth and width of the recess were the same as those of the battery A1a. The height of the regular hexagon was 0.8 mm.

図６に示すような円状と放射状との組み合わせの凹部を形成したこと以外、電池Ａ１ａと同様に、試験電池Ａ１ｃを作製した。凹部の深さと幅は、電池Ａ１ａと同じとした。円状の凹部の直径は２．０ｍｍとした。   A test battery A1c was produced in the same manner as the battery A1a, except that a concave portion having a combination of a circular shape and a radial shape as shown in FIG. 6 was formed. The depth and width of the recess were the same as those of the battery A1a. The diameter of the circular recess was 2.0 mm.

図７に示すような円状の凹部だけを形成したこと以外、電池Ａ１ａと同様に、試験電池Ａ１ｄを作製した。凹部の深さと幅は、電池Ａ１ａと同じとした。円状の凹部の直径は２．０ｍｍとした。
ただし、負極成型体６とリチウム箔とを圧着する際に、負極成型体を支持する冶具または負極成型体を押圧する治具の表面に凹部を設けた。その結果、負極成型体６とリチウム箔との圧着時に、円の外周に向かう放射状の亀裂が生じた。なお、負極成型体６とリチウム箔とを圧着する際に、冶具の表面に凸部を設けた場合にも、同様に、円の外周に向かう放射状の亀裂が生じた。 A test battery A1d was produced in the same manner as the battery A1a, except that only a circular recess as shown in FIG. 7 was formed. The depth and width of the recess were the same as those of the battery A1a. The diameter of the circular recess was 2.0 mm.
However, when the negative electrode molded body 6 and the lithium foil were pressure-bonded, a recess was provided on the surface of a jig for supporting the negative electrode molded body or a jig for pressing the negative electrode molded body. As a result, a radial crack toward the outer periphery of the circle occurred when the negative electrode molded body 6 and the lithium foil were pressed. In addition, when the negative electrode molded body 6 and the lithium foil were pressure-bonded, a radial crack toward the outer periphery of the circle was generated in the same manner even when a convex portion was provided on the surface of the jig.

《実施例２》
負極成型体６の凹部を有する方の平面部を、セパレータ側（図１の下側）に配したこと以外、実施例１と同様の方法で、電池Ａ２を作製した。 Example 2
A battery A2 was produced in the same manner as in Example 1, except that the flat part having the concave portion of the molded negative electrode 6 was disposed on the separator side (lower side in FIG. 1).

《実施例３》
負極成型体の作製時に、他方の金型の表面にも一方の金型と同じ格子状の凸部を設け、負極成型体の両方の平面部に０．８ｍｍ間隔の格子状の凹部を形成した。ただし、図８および図９に示すように、一方の平面部が有する凹部と他方の平面部が有する凹部とが対向しないように、それぞれの位置をずらした。この負極成型体を用いたこと以外、実施例１と同様の方法で、電池Ａ３を作製した。 Example 3
During the production of the negative electrode molded body, the surface of the other mold was also provided with the same grid-like convex portion as that of one mold, and the grid-like concave portions with an interval of 0.8 mm were formed on both flat portions of the negative electrode molded body . However, as shown in FIG. 8 and FIG. 9, the respective positions are shifted so that the concave portion of one flat surface portion does not face the concave portion of the other flat surface portion. A battery A3 was produced in the same manner as in Example 1 except that this molded negative electrode was used.

《実施例４》
図１０および図１１に示すように、一方の平面部が有する凹部と他方の平面部が有する凹部とを対向させたこと以外、実施例３と同様の方法で、電池Ａ４を作製した。 Example 4
As shown in FIGS. 10 and 11, a battery A4 was produced in the same manner as in Example 3, except that the concave portion included in one flat portion and the concave portion included in the other flat portion were opposed to each other.

《実施例５》
負極缶２の負極成型体６との対向面に、高さおよび幅０．０５ｍｍの凸部９を、間隔０．８ｍｍの格子状のパターンで、負極缶の成型時に設けたこと以外は、実施例１と同様の方法で、電池Ａ５を作製した。負極成型体には凹部を形成しなかった。 Example 5
Except that the convex portion 9 having a height and width of 0.05 mm is provided on the surface of the negative electrode can 2 facing the negative electrode molded body 6 in a grid pattern with a spacing of 0.8 mm, when the negative electrode can is molded. A battery A5 was produced in the same manner as in Example 1. No recess was formed in the negative electrode molded body.

《実施例６》
格子状の凸部を有さない金型を用いて、両方の平面部に凹部を有さない負極成型体６を作製した。この負極成型体６を、図１２〜１３に示すように、間隔０．８ｍｍの格子状のパターンに沿って、カッターナイフで２１個に分割した。電池構成時に、分割された負極成型体をリチウム箔上で再整列させたこと以外、実施例１と同様の方法で、電池Ａ６を作製した。 Example 6
Using a mold that does not have a grid-like convex part, a negative electrode molded body 6 that does not have a concave part on both planar parts was produced. As shown in FIGS. 12 to 13, the molded negative electrode 6 was divided into 21 pieces with a cutter knife along a lattice-like pattern with an interval of 0.8 mm. A battery A6 was produced in the same manner as in Example 1 except that the divided negative electrode molded body was rearranged on the lithium foil at the time of battery construction.

《実施例７》
両方の平面部に凹部を有さない負極成型体６を作製した。負極成型体６にリチウム箔１０を圧着する際には、図１４に示すように、リチウム箔１０を押圧する治具１１と、負極成型体６を支持する治具１２とを用いた。また、負極成型体６を支持する治具１２の表面に、高さおよび幅０．０５ｍｍの凸部１３を、間隔０．８ｍｍの格子状のパターンで形成した。よって、負極成型体６とリチウム箔１０との圧着時に、凸部１３を起点として、負極成型体に厚さ方向の亀裂８が生じた。その他は、実施例１と同様の方法で、電池Ａ７を作製した。 Example 7
A negative electrode molded body 6 having no concave portions on both plane portions was produced. When the lithium foil 10 was pressure-bonded to the molded negative electrode 6, as shown in FIG. 14, a jig 11 that pressed the lithium foil 10 and a jig 12 that supported the molded negative electrode 6 were used. Moreover, the convex part 13 of height and width 0.05mm was formed in the surface of the jig | tool 12 which supports the negative electrode molded object 6 with the grid | lattice-like pattern of a 0.8 mm space | interval. Therefore, when the negative electrode molded body 6 and the lithium foil 10 were pressure-bonded, cracks 8 in the thickness direction occurred in the negative electrode molded body starting from the convex portion 13. Otherwise, the battery A7 was produced in the same manner as in Example 1.

《実施例８》
両方の平面部に凹部を有さない負極成型体６を作製した。負極成型体６にリチウム箔１０を圧着する際には、図１５に示すように、リチウム箔１０を押圧する治具１１と、負極成型体６を支持する治具１２とを用いた。また、負極成型体６を支持する治具１２の表面において、直径０．７〜１．４ｍｍの領域に、深さ１．０ｍｍの凹部１４を同心円状に形成した。よって、負極成型体６とリチウム箔１０との圧着時に、凹部１４を起点として、負極成型体に厚さ方向の亀裂８が生じた。その他は、実施例１と同様の方法で、電池Ａ８を作製した。 Example 8
A negative electrode molded body 6 having no concave portions on both plane portions was produced. When the lithium foil 10 was pressure-bonded to the molded negative electrode 6, as shown in FIG. 15, a jig 11 for pressing the lithium foil 10 and a jig 12 for supporting the molded negative electrode 6 were used. In addition, on the surface of the jig 12 that supports the molded negative electrode 6, a recess 14 having a depth of 1.0 mm was formed concentrically in a region having a diameter of 0.7 to 1.4 mm. Therefore, when the molded negative electrode 6 and the lithium foil 10 were bonded, cracks 8 in the thickness direction occurred in the molded negative electrode starting from the recesses 14. Otherwise, the battery A8 was produced in the same manner as in Example 1.

《実施例９》
両方の平面部に凹部を有さない負極成型体６を作製した。負極缶２の負極成型体６との対向面には、予めリチウム箔１０を圧着した。負極成型体６にリチウム箔１０を圧着する際には、図１６に示すように、負極成型体６を押圧する治具１１を用いた。また、負極成型体６を押圧する治具１１の表面に、高さおよび幅０．０５ｍｍの凸部１５を、間隔０．８ｍｍの格子状のパターンで形成した。リチウム箔１０の上に負極成型体６を載置し、凸部を有する治具で負極成型体６を押圧して、リチウム箔１０圧着した。その際、凸部１５を起点として、負極成型体６に厚さ方向の亀裂８が生じた。その他は、実施例１と同様の方法で、電池Ａ９を作製した。 Example 9
A negative electrode molded body 6 having no concave portions on both plane portions was produced. Lithium foil 10 was previously pressure-bonded to the surface of the negative electrode can 2 facing the negative electrode molded body 6. When the lithium foil 10 was pressure bonded to the negative electrode molded body 6, a jig 11 for pressing the negative electrode molded body 6 was used as shown in FIG. 16. Moreover, the convex part 15 of height and width 0.05mm was formed in the surface of the jig | tool 11 which presses the negative electrode molded object 6 with the grid | lattice pattern of the space | interval of 0.8 mm. The negative electrode molded body 6 was placed on the lithium foil 10, the negative electrode molded body 6 was pressed with a jig having a convex portion, and the lithium foil 10 was pressure bonded. At that time, a crack 8 in the thickness direction occurred in the molded negative electrode 6 starting from the convex portion 15. Otherwise, the battery A9 was produced in the same manner as in Example 1.

《実施例１０》
両方の平面部に凹部を有さない負極成型体６を作製した。負極缶２の負極成型体６との対向面には、予めリチウム箔１０を圧着した。負極成型体６にリチウム箔１０を圧着する際には、図１７に示すように、負極成型体６を押圧する治具１１を用いた。また、負極成型体６を押圧する治具１１の表面において、直径０．７〜１．４ｍｍの領域に、深さ１．０ｍｍの凹部１６を同心円状に形成した。リチウム箔１０の上に負極成型体６を載置し、凹部を有する治具で負極成型体６を押圧して、リチウム箔１０圧着した。その際、凹部１６を起点として、負極成型体６に厚さ方向の亀裂８が生じた。その他は、実施例１と同様の方法で、電池Ａ１０を作製した。 Example 10
A negative electrode molded body 6 having no concave portions on both plane portions was produced. Lithium foil 10 was previously pressure-bonded to the surface of the negative electrode can 2 facing the negative electrode molded body 6. When the lithium foil 10 was pressure bonded to the negative electrode molded body 6, as shown in FIG. 17, a jig 11 that presses the negative electrode molded body 6 was used. In addition, on the surface of the jig 11 that presses the molded negative electrode 6, a recess 16 having a depth of 1.0 mm was formed concentrically in a region having a diameter of 0.7 to 1.4 mm. The negative electrode molded body 6 was placed on the lithium foil 10, the negative electrode molded body 6 was pressed with a jig having a recess, and the lithium foil 10 was pressure bonded. At that time, a crack 8 in the thickness direction occurred in the molded negative electrode 6 starting from the recess 16. Otherwise, the battery A10 was produced in the same manner as in Example 1.

《比較例１》
両方の平面部に凹部を有さない負極成型体６を作製し、これを用いたこと以外、実施例１と同様の方法で、電池Ａ０ａを作製した。 << Comparative Example 1 >>
A battery A0a was produced in the same manner as in Example 1 except that a molded negative electrode 6 having no recesses in both planar portions was produced and this was used.

《比較例２》
リチウム箔を貼り付ける位置を、負極成型体の負極缶側に変えたこと以外、比較例１と同様の方法で、電池Ａ０ｂを作製した。 << Comparative Example 2 >>
A battery A0b was produced in the same manner as in Comparative Example 1, except that the position where the lithium foil was applied was changed to the negative electrode can side of the negative electrode molded body.

［評価］
上述した各電池に対し、以下の方法で、容量維持率および内部抵抗上昇率の評価を行った。
２０℃に設定した恒温室の中で、定電流充放電を、充電電流、放電電流ともに０．０５Ｃ（１Ｃは１時間率電流）で、電池電圧２．０〜３．３Ｖの範囲で、１００サイクル繰り返した。このときの１サイクル目に対する１００サイクル目の放電容量の比率を容量維持率とした。また、１サイクル目に対する１００サイクル目の電池内部抵抗の比率より、内部抵抗上昇率を算出した。電池内部抵抗は、１ＫＨｚ交流インピーダンス法で測定した。結果を表１に示す。また、１００サイクル後の電池を断面Ｘ線ＣＴにより観察した。実施例１〜６および比較例１の負極成型体が有する亀裂の状態を図１８〜２４に示す。 [Evaluation]
For each battery described above, the capacity maintenance rate and the internal resistance increase rate were evaluated by the following method.
In a constant temperature room set at 20 ° C., constant current charge / discharge is carried out at a charge voltage and a discharge current of 0.05 C (1 C is a one hour rate current) and a battery voltage in the range of 2.0 to 3.3 V, 100 The cycle was repeated. The ratio of the discharge capacity at the 100th cycle to the first cycle at this time was defined as the capacity retention rate. Further, the rate of increase in internal resistance was calculated from the ratio of the battery internal resistance at the 100th cycle to the first cycle. The battery internal resistance was measured by the 1 KHz AC impedance method. The results are shown in Table 1. Further, the battery after 100 cycles was observed by cross-sectional X-ray CT. The state of the crack which the negative electrode molded object of Examples 1-6 and Comparative Example 1 has is shown in FIGS.

Figure 2007157704
Figure 2007157704

まず、電池Ａ０ａについて述べる（図２４参照）。電池Ａ０ａの断面Ｘ線ＣＴによると、負極成型体６の亀裂８は、成型体の面方向（厚さ方向に垂直な方向）に多く形成されていた。このことは、成型体の厚さ方向における集電経路の連続性が断絶されていることを示している。また、成型体のセパレータ側の中心付近では、成型体が比較的細かく分割されていた。これは、負極活物質とリチウムとの合金化がリチウム箔を配置したセパレータ側から始まることや、成型体の中心付近に応力が蓄積しやすいことと関連すると考えられる。そして、１００サイクル後の容量維持率は６７％と低く、電池の内部抵抗上昇率は５０％と大きかった。
電池Ａ０ｂの負極成型体では、１００サイクル後の容量維持率は４２％と更に低く、電池の内部抵抗上昇率は８７％とさらに大きかった。リチウム箔を貼り付けた側の細かく分割された面が、負極缶側と対向しており、成型体と負極缶との間の電気的接触が低下したものと考えられる。 First, the battery A0a will be described (see FIG. 24). According to the cross-sectional X-ray CT of the battery A0a, many cracks 8 of the negative electrode molded body 6 were formed in the surface direction of the molded body (direction perpendicular to the thickness direction). This has shown that the continuity of the current collection path | route in the thickness direction of a molded object is interrupted. Further, the molded body was relatively finely divided in the vicinity of the center of the molded body on the separator side. This is considered to be related to the fact that the alloying of the negative electrode active material and lithium starts from the separator side where the lithium foil is disposed, and stress is likely to accumulate near the center of the molded body. The capacity maintenance rate after 100 cycles was as low as 67%, and the internal resistance increase rate of the battery was as high as 50%.
In the molded negative electrode of the battery A0b, the capacity retention rate after 100 cycles was even lower, 42%, and the rate of increase in internal resistance of the battery was 87%. The finely divided surface on the side to which the lithium foil is attached is opposed to the negative electrode can side, and it is considered that the electrical contact between the molded body and the negative electrode can is reduced.

電池Ａ１ａの負極成型体では、厚さ方向における集電経路の連続性の断絶が大幅に抑制されていた。また、成型体に生じた亀裂の約５０％が凹部７を起点とするものであった（図１８参照）。そして、１００サイクル後の容量維持率は９０％と高く、電池の内部抵抗上昇率は１５％と低く良好であった。これは、負極成型体６の負極缶２側に凹部を形成したことにより、成型体の厚さ方向に優先的に亀裂が生じたことと関連する。凹部７によって、分割により生じる区分の大きさと形状が適正化され、特に厚さ方向の集電経路の連続性が効果的に維持されたものと考えられる。電池Ａ１ｂ、電池Ａ１ｃおよび電池Ａ１ｄについても同様の結果が得られた。   In the negative electrode molded body of the battery A1a, the disconnection of the continuity of the current collecting path in the thickness direction was significantly suppressed. Further, about 50% of the cracks generated in the molded body originated from the recesses 7 (see FIG. 18). The capacity maintenance rate after 100 cycles was as high as 90%, and the rate of increase in internal resistance of the battery was as low as 15% and was good. This is related to the fact that a crack was preferentially generated in the thickness direction of the molded body by forming the concave portion on the negative electrode can 2 side of the molded negative electrode 6. It is considered that the size and shape of the sections generated by the division are optimized by the recesses 7, and in particular, the continuity of the current collecting path in the thickness direction is effectively maintained. Similar results were obtained for the batteries A1b, A1c, and A1d.

電池Ａ２の負極成型体では、厚さ方向における集電経路の連続性の断絶が、電池Ａ１ａに比べて、更に抑制されていた。また、成型体に生じた亀裂の約６０％が凹部７を起点とするものであった（図１９参照）。ただし、電池Ａ１ａに比べて、負極缶側（図１９の上側）で成型体が細分化する傾向が認められた。容量維持率と抵抗上昇率は、電池Ａ０ａに比べると大幅に改善したが、電池Ａ１ａに比べるとやや劣っていた。これは、負極端子を兼ねる負極缶側での成型体の細分化が、成型体−負極缶間の接触抵抗の増大を招いたためと考えられる。負極缶側で成型体が細分化したのは、凹部がセパレータ側にあるためであり、成型体の負極缶側への凹部の影響が小さくなったものと考えられる。   In the negative electrode molded body of the battery A2, the continuity of the current collecting path in the thickness direction was further suppressed compared to the battery A1a. Further, about 60% of the cracks generated in the molded body originated from the recesses 7 (see FIG. 19). However, compared with battery A1a, the tendency for a molded object to subdivide by the negative electrode can side (upper side of FIG. 19) was recognized. The capacity retention rate and the resistance increase rate were greatly improved as compared with the battery A0a, but were slightly inferior as compared with the battery A1a. This is presumably because the fragmentation of the molded body on the negative electrode can side also serving as the negative electrode terminal caused an increase in contact resistance between the molded body and the negative electrode can. The reason why the molded body was subdivided on the negative electrode can side is that the concave portion is on the separator side, and it is considered that the influence of the concave portion on the negative electrode can side of the molded body was reduced.

電池Ａ３の負極成型体では、亀裂の約８０％が両方の平面部の凹部を起点として生じていた（図２０参照）。容量維持率と内部抵抗上昇率は、電池Ａ０ａに比べると大幅に改善したが、電池Ａ１および電池Ａ２に比べると劣っていた。これは、両方の平面部の凹部が互いに対向していないためであり、上面および下面の凹部間の亀裂が、成型体の厚さ方向に対して傾斜し、厚さ方向の集電経路の連続性が部分的に失われたものと考えられる。   In the molded negative electrode of the battery A3, about 80% of the cracks originated from the concave portions of both flat portions (see FIG. 20). The capacity retention rate and the rate of increase in internal resistance were greatly improved as compared to the battery A0a, but were inferior to those of the battery A1 and the battery A2. This is because the concave portions of both the flat portions are not opposed to each other, and the crack between the concave portions on the upper surface and the lower surface is inclined with respect to the thickness direction of the molded body, and the current collecting path in the thickness direction is continuous. It is thought that sex was partially lost.

電池Ａ４の負極成型体では、亀裂の約９０％が両方の平面部の凹部を起点として生じていた（図２１参照）。容量維持率と内部抵抗上昇率は、それぞれ９５％および８％であり、最も良好な結果となった。両方の平面部の凹部が互いに対向しているため、亀裂が成型体の厚さ方向とほぼ平行となり、厚さ方向の集電経路の連続性が保持されたものと考えられる。   In the molded negative electrode of the battery A4, about 90% of the cracks originated from the concave portions of both flat portions (see FIG. 21). The capacity retention rate and the internal resistance increase rate were 95% and 8%, respectively, and the best results were obtained. Since the concave portions of both flat portions are opposed to each other, it is considered that the crack is almost parallel to the thickness direction of the molded body, and the continuity of the current collecting path in the thickness direction is maintained.

電池Ａ５の負極成型体の分割状況は、電池Ａ１ａとほぼ同様であった（図２２参照）。ただし、正極成型体の一部にも割れが認められた。容量維持率と抵抗上昇率は、電池Ａ０ａに比べると大幅に改善したが、電池Ａ１ａに比べてやや劣る結果となった。これは、充電時に負極成型体が膨張し、正極成型体に圧力が印加された際に、正極成型体が割れたり、セパレータやリチウム箔が押しつぶされたりしたためと考えられる。   The division state of the molded negative electrode of the battery A5 was almost the same as that of the battery A1a (see FIG. 22). However, cracks were also observed in a part of the molded positive electrode. The capacity retention rate and the resistance increase rate were greatly improved as compared with the battery A0a, but were slightly inferior to those of the battery A1a. This is considered to be because the negative electrode molded body expanded during charging and the positive electrode molded body was cracked or the separator or lithium foil was crushed when pressure was applied to the positive electrode molded body.

電池Ａ６の負極成型体には、新たな亀裂がほとんど発生せず、厚さ方向の連続性が保持されていた（図２３参照）。電池Ａ４と同等の容量維持率と内部抵抗上昇率であった。   In the molded negative electrode of the battery A6, new cracks hardly occurred and continuity in the thickness direction was maintained (see FIG. 23). The capacity retention rate and internal resistance increase rate were the same as those of Battery A4.

電池Ａ７および電池Ａ８の電池特性は、電池Ａ５に比べてやや良好であった。これは、負極成型体がリチウムと合金化する前に、既に成型体に亀裂が生じていたためである（図１４、１５参照）。これにより、リチウムと合金化する際の負極成型体の割れが抑制されたと考えられる。また、正極成型体の割れが生じていないためと考えられる。   The battery characteristics of the battery A7 and the battery A8 were slightly better than the battery A5. This is because the molded body had already cracked before the anode molded body was alloyed with lithium (see FIGS. 14 and 15). Thereby, it is considered that cracking of the molded negative electrode during alloying with lithium was suppressed. Moreover, it is thought that the positive electrode molded body is not cracked.

電池Ａ９および電池Ａ１０の電池特性は、電池Ａ７および電池Ａ８に比べてやや劣っていた。これは、電池Ａ０ｂの電池特性が電池Ａ０ａに比べて劣ることと同様であり、皮膜形成や成型体の割れのため、成型体−負極缶の間の抵抗が高くなったためと考えられる（図１６、１７参照）。   The battery characteristics of the batteries A9 and A10 were slightly inferior to those of the batteries A7 and A8. This is similar to the fact that the battery characteristics of the battery A0b are inferior to those of the battery A0a, and it is considered that the resistance between the molded body and the negative electrode can is increased due to the formation of a film and the cracking of the molded body (FIG. 16). 17).

以上の結果より、負極成型体の平面部に凹部を形成し、または、負極缶の負極成型体との対向面に凸部を形成し、または、予め負極成型体に厚さ方向の亀裂を形成することにより、負極成型体の厚さ方向における集電経路の連続性を確保することが可能であり、容量維持率の向上、抵抗上昇率の抑制に効果があることが確認できた。また、電池Ａ４のように、両方の平面部に互いに対向する凹部を形成して充放電時に負極成型体を分割させることにより、電池Ａ６のように、予め分割された成型体を用いる場合と同等の性能が得られることが確認できた。   Based on the above results, a concave portion is formed in the flat portion of the negative electrode molded body, or a convex portion is formed on the surface of the negative electrode can facing the negative electrode molded body, or a crack in the thickness direction is previously formed in the negative electrode molded body. By doing so, it was possible to ensure the continuity of the current collecting path in the thickness direction of the molded negative electrode, and it was confirmed that there was an effect in improving the capacity retention rate and suppressing the resistance increase rate. Further, as in the case of the battery A4, by forming recesses facing each other on both flat portions and dividing the negative electrode molded body during charging and discharging, it is equivalent to the case of using a previously divided molded body as in the case of the battery A6. It was confirmed that the performance of

《実施例１１》
負極活物質として、Ｓｉ−Ｔｉ合金の代わりに鱗片状黒鉛（平均粒径１０μｍ）を用いたこと以外、実施例４と同様の方法で、電池Ｂ４を作製した。すなわち、本実施例では、両方の平面部に互いに対向する凹部を有する負極成型体を用いた。負極合剤におけるカーボンブラックとポリアクリル酸の含有量も実施例１と同じとした。 Example 11
A battery B4 was produced in the same manner as in Example 4 except that scaly graphite (average particle size 10 μm) was used as the negative electrode active material instead of the Si—Ti alloy. In other words, in this example, a molded negative electrode having concave portions facing each other on both plane portions was used. The contents of carbon black and polyacrylic acid in the negative electrode mixture were also the same as in Example 1.

《比較例３》
負極活物質として、Ｓｉ−Ｔｉ合金の代わりに鱗片状黒鉛（平均粒径１０μｍ）を用いたこと以外、比較例１と同様の方法で、電池Ｂ０を作製した。すなわち、本比較例では、両方の平面部に凹部を有さない負極成型体を用いた。 << Comparative Example 3 >>
A battery B0 was produced in the same manner as in Comparative Example 1, except that scaly graphite (average particle size 10 μm) was used instead of the Si—Ti alloy as the negative electrode active material. That is, in this comparative example, a negative electrode molded body having no concave portions on both flat portions was used.

《実施例１２》
厚さ０．２５ｍｍのアルミニウム板を打ち抜いたものを負極成型体として用いたこと以外、実施例４と同様の方法で、電池Ｃ４を作製した。すなわち、本実施例では、両方の平面部に互いに対向する凹部を有する負極成型体を用いた。ＸＲＤの観察結果（ピーク位置と半価幅）より、Ｓｃｈｅｒｒｅｒの式を用いてアルミニウムの結晶子サイズを計算すると、３６ｎｍであった。 Example 12
A battery C4 was produced in the same manner as in Example 4, except that a punched out aluminum plate having a thickness of 0.25 mm was used as the molded negative electrode. In other words, in this example, a molded negative electrode having concave portions facing each other on both plane portions was used. From the observation results of XRD (peak position and half width), the crystallite size of aluminum was calculated using Scherrer's formula and found to be 36 nm.

《比較例４》
厚さ０．２５ｍｍのアルミニウム板を打ち抜いたものをそのまま負極成型体として用いたこと以外、比較例１と同様の方法で電池Ｃ０を作製した。すなわち、本比較例では、両方の平面部に凹部を有さない負極成型体を用いた。 << Comparative Example 4 >>
A battery C0 was produced in the same manner as in Comparative Example 1, except that a punched aluminum plate having a thickness of 0.25 mm was used as it was as a molded negative electrode. That is, in this comparative example, a negative electrode molded body having no concave portions on both flat portions was used.

《実施例１３》
負極活物質の合成において、Ｓｉ粉末とＴｉ粉末との混合物の代わりにＳｉ粉末のみを用い、実施例１と同様に振動ボールミル装置でメカニカルアロイングを行ったこと以外、実施例４と同様の方法で、電池Ｄ４を作製した。すなわち、本実施例では、両方の平面部に互いに対向する凹部を有する負極成型体を用いた。ＸＲＤの観察結果（ピーク位置と半価幅）と、Ｓｃｈｅｒｒｅｒの式とを用い、ケイ素の結晶子サイズを計算すると、１０ｎｍであった。 Example 13
In the synthesis of the negative electrode active material, the same method as in Example 4 except that only Si powder was used in place of the mixture of Si powder and Ti powder, and mechanical alloying was performed with a vibrating ball mill apparatus as in Example 1. Thus, a battery D4 was produced. In other words, in this example, a molded negative electrode having concave portions facing each other on both plane portions was used. The crystallite size of silicon was calculated to be 10 nm using the XRD observation results (peak position and half width) and Scherrer's equation.

《比較例５》
実施例１３と同じ負極活物質を用いたこと以外、比較例１と同様の方法で、電池Ｄ０を作製した。すなわち、本比較例では、両方の平面部に凹部を有さない負極成型体を用いた。 << Comparative Example 5 >>
A battery D0 was produced in the same manner as in Comparative Example 1, except that the same negative electrode active material as in Example 13 was used. That is, in this comparative example, a negative electrode molded body having no concave portions on both flat portions was used.

《実施例１４》
負極活物質の合成において、Ｓｉ粉末とＴｉ粉末との混合物の代わりにＳｎ粉末のみを用い、実施例１と同様に振動ボールミル装置でメカニカルアロイングを行ったこと以外、実施例４と同様の方法で、電池Ｅ４を作製した。すなわち、本実施例では、両方の平面部に互いに対向する凹部を有する負極成型体を用いた。ＸＲＤの観察結果（ピーク位置と半価幅）と、Ｓｃｈｅｒｒｅｒの式とを用い、スズの結晶子サイズを計算すると、１５ｎｍであった。 Example 14
In the synthesis of the negative electrode active material, the same method as in Example 4 except that only Sn powder was used in place of the mixture of Si powder and Ti powder, and mechanical alloying was performed with a vibrating ball mill apparatus as in Example 1. Thus, a battery E4 was produced. In other words, in this example, a molded negative electrode having concave portions facing each other on both plane portions was used. Using the XRD observation results (peak position and half width) and Scherrer's equation, the crystallite size of tin was calculated to be 15 nm.

《比較例６》
実施例１４と同じ負極活物質を用いたこと以外、比較例１と同様の方法で、電池Ｅ０を作製した。すなわち、本比較例では、両方の平面部に凹部を有さない負極成型体を用いた。 << Comparative Example 6 >>
A battery E0 was produced in the same manner as in Comparative Example 1, except that the same negative electrode active material as in Example 14 was used. That is, in this comparative example, a negative electrode molded body having no concave portions on both flat portions was used.

《実施例１５》
負極活物質の合成において、Ｓｉ粉末とＴｉ粉末との混合物の代わりにＳｉＯ粉末を用い、実施例１と同様に振動ボールミル装置でメカニカルアロイングを行ったこと以外、実施例４と同様の方法で、電池Ｆ４を作製した。すなわち、本実施例では、両方の平面部に互いに対向する凹部を有する負極成型体を用いた。ＸＲＤの観察結果（ピーク位置と半価幅）と、Ｓｃｈｅｒｒｅｒの式とを用い、結晶子サイズを計算すると、１２ｎｍであった。 Example 15
In the synthesis of the negative electrode active material, SiO powder was used instead of the mixture of Si powder and Ti powder, and the mechanical alloying was performed with a vibrating ball mill apparatus in the same manner as in Example 1 in the same manner as in Example 4. A battery F4 was produced. In other words, in this example, a molded negative electrode having concave portions facing each other on both plane portions was used. Using the XRD observation results (peak position and half width) and Scherrer's equation, the crystallite size was calculated to be 12 nm.

《比較例７》
実施例１５と同じ負極活物質を用いたこと以外、比較例１と同様の方法で、電池Ｆ０を作製した。すなわち、本比較例では、両方の平面部に凹部を有さない負極成型体を用いた。 << Comparative Example 7 >>
A battery F0 was produced in the same manner as in Comparative Example 1, except that the same negative electrode active material as in Example 15 was used. That is, in this comparative example, a negative electrode molded body having no concave portions on both flat portions was used.

《実施例１６》
負極活物質の合成において、Ｓｉ粉末とＴｉ粉末との混合物の代わりにＳｎＯ2粉末を用い、実施例１と同様に振動ボールミル装置でメカニカルアロイングを行ったこと以外、実施例４と同様の方法で、電池Ｇ４を作製した。すなわち、本実施例では、両方の平面部に互いに対向する凹部を有する負極成型体を用いた。ＸＲＤの観察結果（ピーク位置と半価幅）と、Ｓｃｈｅｒｒｅｒの式とを用い、結晶子サイズを計算すると、１８ｎｍであった。 Example 16
In the synthesis of the negative electrode active material, the same method as in Example 4 except that SnO 2 powder was used instead of the mixture of Si powder and Ti powder, and mechanical alloying was performed with a vibrating ball mill apparatus as in Example 1. Thus, a battery G4 was produced. In other words, in this example, a molded negative electrode having concave portions facing each other on both plane portions was used. Using the XRD observation results (peak position and half width) and Scherrer's formula, the crystallite size was calculated to be 18 nm.

《比較例８》
実施例１６と同じ負極活物質を用いたこと以外、比較例１と同様の方法で、電池Ｇ０を作製した。すなわち、本比較例では、両方の平面部に凹部を有さない負極成型体を用いた。 << Comparative Example 8 >>
A battery G0 was produced in the same manner as in Comparative Example 1, except that the same negative electrode active material as in Example 16 was used. That is, in this comparative example, a negative electrode molded body having no concave portions on both flat portions was used.

《実施例１７》
負極活物質の合成において、Ｓｉ粉末およびＮｉ粉末を、元素モル比が７４．１：２５．９となるように混合し、実施例１と同様に振動ボールミル装置でメカニカルアロイングを行ったこと以外、実施例４と同様の方法で、電池Ｈ４を作製した。すなわち、本実施例では、Ｓｉ−Ｔｉ合金の代わりにＳｉ−Ｎｉ合金を用い、両方の平面部に互いに対向する凹部を有する負極成型体を作製した。
ただし、負極の作製において、Ｓｉ−Ｎｉ合金と、導電剤であるカーボンブラックと、結着剤であるポリアクリル酸とを、重量比で１１５：２０：１０の割合で混合し、負極合剤を得た。 Example 17
In the synthesis of the negative electrode active material, Si powder and Ni powder were mixed so that the element molar ratio was 74.1: 25.9, and mechanical alloying was performed using a vibrating ball mill apparatus as in Example 1. A battery H4 was produced in the same manner as in Example 4. That is, in this example, a Si—Ni alloy was used in place of the Si—Ti alloy, and a negative electrode molded body having recesses facing each other on both plane portions was produced.
However, in the preparation of the negative electrode, Si—Ni alloy, carbon black as a conductive agent, and polyacrylic acid as a binder are mixed at a weight ratio of 115: 20: 10, and the negative electrode mixture is mixed. Obtained.

ＸＲＤの観察結果より、Ｓｉ−Ｎｉ合金は、少なくともＳｉ相とＮｉＳｉ2相とを含むことが判明した。ただし、ピーク位置が重なるためＳｉ相とＮｉＳｉ2相との分離は不可能であった。ピーク位置と半価幅と、Ｓｃｈｅｒｒｅｒの式とを用い、合金の結晶子サイズを計算すると、１２ｎｍであった。Ｎｉ−Ｓｉ相とＳｉ相との重量比は、Ｎｉが全てＮｉＳｉ2を形成したと仮定すると、８２．６：１７．４であった。なお、Ｎｉ−Ｓｉ合金の組成は、その膨張後の体積が、実施例１のＴｉ−Ｓｉ合金の膨張後の体積と同一になるように決定した。また、負極合剤の組成は、負極活物質と導電剤と結着剤との体積比が実施例４の負極合剤と同一になるように設計した。 From the XRD observation results, it was found that the Si—Ni alloy contains at least a Si phase and a NiSi 2 phase. However, since the peak positions overlap, it was impossible to separate the Si phase and the NiSi 2 phase. When the crystallite size of the alloy was calculated using the peak position, the half width, and the Scherrer equation, it was 12 nm. The weight ratio of the NiSi phase and the Si phase, assuming Ni was formed all NiSi 2, 82.6: 17.4. The composition of the Ni—Si alloy was determined such that the volume after expansion was the same as the volume after expansion of the Ti—Si alloy of Example 1. The composition of the negative electrode mixture was designed so that the volume ratio of the negative electrode active material, the conductive agent, and the binder was the same as that of the negative electrode mixture of Example 4.

《比較例９》
実施例１７と同じ負極合剤を用いたこと以外、比較例１と同様の方法で、電池Ｈ０を作製した。すなわち、本比較例では、両方の平面部に凹部を有さない負極成型体を用いた。
各電池に関し、容量維持率および内部抵抗上昇率の評価を行った。結果を表２に示す。 << Comparative Example 9 >>
A battery H0 was produced in the same manner as in Comparative Example 1, except that the same negative electrode mixture as in Example 17 was used. That is, in this comparative example, a negative electrode molded body having no concave portions on both flat portions was used.
For each battery, the capacity maintenance rate and the internal resistance increase rate were evaluated. The results are shown in Table 2.

Figure 2007157704
Figure 2007157704

電池Ｂ４および電池Ｂ０は、初期容量が他の電池の６０％程度と小さかった。電池Ｂ４および電池Ｂ０は、凹部の有無にかかわらず、負極成型体の割れはほとんど起こらず、良好な容量維持率と低い内部抵抗上昇率を示した。これは、充放電時における活物質の体積あたりの容量および膨張収縮量が小さいことも一因であるが、主要因は負極成型体の体積あたりの容量および膨張収縮量が小さいためであると考えられる。充電後の負極成型体の見かけ体積（内部空隙を含む体積）は、充電前の１．２倍であった。   Battery B4 and battery B0 had initial capacities as small as about 60% of other batteries. In Battery B4 and Battery B0, cracking of the molded negative electrode hardly occurred regardless of the presence or absence of the recess, and a good capacity retention rate and a low internal resistance increase rate were exhibited. This is partly because the capacity per volume and expansion / contraction amount of the active material during charging / discharging are small, but the main factor is considered to be because the capacity per volume and expansion / contraction amount of the negative electrode molded body is small. It is done. The apparent volume (volume including internal voids) of the molded negative electrode after charging was 1.2 times that before charging.

電池Ｃ４およびＣ０は、凹部の有無にかかわらず、負極成型体の割れが多く発生し、厚さ方向における集電経路の連続性の断絶が多く認められた。また、電池Ｃ４およびＣ０の容量維持率は低く、内部抵抗上昇率は大きかった。これは、Ａｌの結晶子サイズが３６ｎｍであり、２０ｎｍよりも大きいためと考えられる。結晶子サイズが大きいと、凹部を起点とする亀裂による負極成型体の分割後も、負極成型体の至る所で破断が発生すると考えられる。なお、充電後の負極成型体の見かけ体積（内部空隙を含む体積）は、充電前の２．０倍であった。   In the batteries C4 and C0, many cracks of the negative electrode molded body occurred regardless of the presence or absence of the recesses, and many interruptions in the continuity of the current collecting path in the thickness direction were observed. Further, the capacity maintenance rates of the batteries C4 and C0 were low, and the rate of increase in internal resistance was large. This is presumably because the crystallite size of Al is 36 nm and is larger than 20 nm. If the crystallite size is large, it is considered that breakage occurs throughout the negative electrode molded body even after the negative electrode molded body is divided by cracks starting from the recesses. In addition, the apparent volume (volume containing an internal space | gap) of the negative electrode molded object after charge was 2.0 times before charge.

実施例１３〜１４の電池では、いずれの活物質を用いた場合でも、厚さ方向における集電経路の連続性の断絶が抑制され、容量維持率の改善と抵抗上昇率の抑制が確認できた。充電後の負極成型体の見かけ体積（内部空隙を含む体積）は、いずれも充電前の１．６倍でほぼ一定であった。これは、負極成型体に貼り付けるリチウム箔の量を一定にしたためと考えられる。   In the batteries of Examples 13 to 14, even when any active material was used, the disconnection of the continuity of the current collecting path in the thickness direction was suppressed, and the improvement of the capacity maintenance rate and the suppression of the resistance increase rate were confirmed. . The apparent volume (volume including internal voids) of the molded negative electrode after charging was 1.6 times that before charging and was almost constant. This is presumably because the amount of lithium foil attached to the molded negative electrode was made constant.

本発明は、特に高容量なＳｉ系材料およびＳｎ系材料を活物質として用いる場合に有効である。Ｓｉ系材料およびＳｎ系材料を含む負極は、構造が安定しにくいが、本発明によれば、負極の構造が安定化する。本発明によれば、従来の炭素材料を用いたリチウム二次電池に比べて大幅な高容量化が可能となり、また、従来のＡｌ板を用いたリチウム二次電池に比べて大幅な長寿命化を図ることができる。   The present invention is particularly effective when high-capacity Si-based materials and Sn-based materials are used as active materials. Although the structure of the negative electrode including the Si-based material and the Sn-based material is difficult to stabilize, according to the present invention, the structure of the negative electrode is stabilized. According to the present invention, the capacity can be significantly increased compared to a lithium secondary battery using a conventional carbon material, and the life can be significantly increased compared to a lithium secondary battery using a conventional Al plate. Can be achieved.

本発明の一実施形態に係るコイン型リチウム二次電池の縦断面図である。It is a longitudinal cross-sectional view of the coin-type lithium secondary battery which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の上面図である。It is a top view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の斜視図である。It is a perspective view of the negative electrode molding concerning one embodiment of the present invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の上面図である。It is a top view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の上面図である。It is a top view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の上面図である。It is a top view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の斜視図である。It is a perspective view of the negative electrode molding concerning one embodiment of the present invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の斜視図である。It is a perspective view of the negative electrode molding concerning one embodiment of the present invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の斜視図である。It is a perspective view of the negative electrode molding concerning one embodiment of the present invention. 本発明の一実施形態に係る負極成型体の断面図である。It is sectional drawing of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極の製造方法を示す断面概念図である。It is a section conceptual diagram showing a manufacturing method of a negative electrode concerning one embodiment of the present invention. 本発明の一実施形態に係る負極の製造方法を示す断面概念図である。It is a section conceptual diagram showing a manufacturing method of a negative electrode concerning one embodiment of the present invention. 本発明の一実施形態に係る負極の製造方法を示す断面概念図である。It is a section conceptual diagram showing a manufacturing method of a negative electrode concerning one embodiment of the present invention. 本発明の一実施形態に係る負極の製造方法を示す断面概念図である。It is a section conceptual diagram showing a manufacturing method of a negative electrode concerning one embodiment of the present invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の一実施形態に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molded object which concerns on one Embodiment of this invention. 本発明の比較例に係る負極成型体の縦断面図である。It is a longitudinal cross-sectional view of the negative electrode molding which concerns on the comparative example of this invention.

符号の説明Explanation of symbols

１ 正極缶
２ 負極缶
３ ガスケット
４ 正極成型体
５ セパレータ
６ 負極成型体
７ 凹部
８ 亀裂
９ 負極缶の凸部
１０ リチウム箔
１１ 押圧治具
１２ 支持治具
１３ 支持治具の凸部
１４ 支持治具の凹部
１５ 押圧治具の凸部
１６ 押圧治具の凹部 DESCRIPTION OF SYMBOLS 1 Positive electrode can 2 Negative electrode can 3 Gasket 4 Positive electrode molded object 5 Separator 6 Negative electrode molded object 7 Concave part 8 Crack 9 Negative electrode can convex part 10 Lithium foil 11 Pressing jig 12 Support jig 13 Convex part of supporting jig 14 Support jig 15 Concave part of pressing jig 16 Concave part of pressing jig

Claims (19)

リチウムの吸蔵および放出が可能な負極活物質を含む負極成型体を含み、
前記負極成型体は、２つの平面部と側面部とを有するコイン型であり、かつ厚さ方向に亀裂を有し、
前記２つの平面部の少なくとも一方が凹部を有し、前記亀裂が前記凹部を起点とする亀裂である、コイン型リチウム二次電池用負極。 Including a molded negative electrode containing a negative electrode active material capable of inserting and extracting lithium;
The negative electrode molded body is a coin type having two plane parts and a side part, and has a crack in the thickness direction,
A negative electrode for a coin-type lithium secondary battery, wherein at least one of the two flat portions has a recess, and the crack is a crack starting from the recess. 前記２つの平面部がそれぞれ前記凹部を有し、一方の平面部が有する凹部と、他方の平面部が有する凹部とが、少なくとも部分的に対向している、請求項１記載のコイン型リチウム二次電池用負極。   2. The coin-type lithium secondary battery according to claim 1, wherein each of the two flat portions has the concave portion, and the concave portion of one flat portion and the concave portion of the other flat portion are at least partially opposed to each other. Negative electrode for secondary battery. 前記凹部が、線状、円状、放射状、格子状、多角形状およびハニカム状よりなる群から選択される少なくとも１つのパターンで形成されている、請求項１記載のコイン型リチウム二次電池用負極。   2. The negative electrode for a coin-type lithium secondary battery according to claim 1, wherein the recess is formed in at least one pattern selected from the group consisting of a linear shape, a circular shape, a radial shape, a lattice shape, a polygonal shape, and a honeycomb shape. . 前記負極活物質が、遷移金属とＳｉとの合金、Ｓｉ、ＳｉＯx（０＜ｘ＜２）、ＳｎおよびＳｎＯx（０＜ｘ≦２）よりなる群から選択される少なくとも１種を含む、請求項１記載のコイン型リチウム二次電池用負極。 The negative electrode active material includes at least one selected from the group consisting of an alloy of transition metal and Si, Si, SiO x (0 <x <2), Sn, and SnO x (0 <x ≦ 2). The negative electrode for coin-type lithium secondary batteries according to claim 1. 前記負極活物質の結晶子サイズが２０ｎｍ以下である、請求項４記載のコイン型リチウム二次電池用負極。   The negative electrode for coin-type lithium secondary batteries according to claim 4, wherein a crystallite size of the negative electrode active material is 20 nm or less. 正極と、前記正極を収容する正極缶と、負極と、前記負極を収容する負極缶、前記正極と前記負極との間に介在するセパレータとを含み、
前記正極は、リチウムの吸蔵および放出が可能な正極活物質を含む正極成型体を含み、
前記負極は、リチウムの吸蔵および放出が可能な負極活物質を含む負極成型体を含み、
前記負極成型体は、２つの平面部と側面部とを有するコイン型であり、かつ厚さ方向に亀裂を有し、前記２つの平面部の少なくとも一方が凹部を有し、前記亀裂が前記凹部を起点とする亀裂である、コイン型リチウム二次電池。 A positive electrode, a positive electrode can containing the positive electrode, a negative electrode, a negative electrode can containing the negative electrode, a separator interposed between the positive electrode and the negative electrode,
The positive electrode includes a positive electrode molded body containing a positive electrode active material capable of inserting and extracting lithium,
The negative electrode includes a molded negative electrode including a negative electrode active material capable of occluding and releasing lithium,
The negative electrode molded body is a coin type having two flat portions and side portions, and has a crack in the thickness direction, at least one of the two flat portions has a recess, and the crack has the recess. A coin-type lithium secondary battery, which is a crack starting from. 前記２つの平面部がそれぞれ前記凹部を有し、一方の平面部が有する凹部と、他方の平面部が有する凹部とが、少なくとも部分的に対向している、請求項６記載のコイン型リチウム二次電池。   The coin-type lithium secondary battery according to claim 6, wherein each of the two flat portions has the concave portion, and the concave portion of one flat portion and the concave portion of the other flat portion are at least partially opposed to each other. Next battery. 前記凹部が、線状、円状、放射状、格子状、多角形状およびハニカム状よりなる群から選択される少なくとも１つのパターンで形成されている、請求項６記載のコイン型リチウム二次電池。   The coin-type lithium secondary battery according to claim 6, wherein the concave portion is formed in at least one pattern selected from the group consisting of a linear shape, a circular shape, a radial shape, a lattice shape, a polygonal shape, and a honeycomb shape. 前記負極活物質が、遷移金属とＳｉとの合金、Ｓｉ、ＳｉＯx（０＜ｘ＜２）、ＳｎおよびＳｎＯx（０＜ｘ≦２）よりなる群から選択される少なくとも１種を含む、請求項６記載のコイン型リチウム二次電池。 The negative electrode active material includes at least one selected from the group consisting of an alloy of transition metal and Si, Si, SiO x (0 <x <2), Sn, and SnO x (0 <x ≦ 2). The coin-type lithium secondary battery according to claim 6. 正極と、前記正極を収容する正極缶と、負極と、前記負極を収容する負極缶、前記正極と前記負極との間に介在するセパレータとを含み、
前記正極は、リチウムの吸蔵および放出が可能な正極活物質を含む正極成型体を含み、
前記負極は、リチウムの吸蔵および放出が可能な負極活物質を含む負極成型体を含み、
前記負極成型体は、２つの平面部と側面部とを有するコイン型であり、かつ厚さ方向に亀裂を有し、前記負極缶は、前記負極成型体と対向する面に凸部を有し、前記亀裂が、前記凸部と前記負極成型体との接触部を起点とする亀裂である、コイン型リチウム二次電池。 A positive electrode, a positive electrode can containing the positive electrode, a negative electrode, a negative electrode can containing the negative electrode, a separator interposed between the positive electrode and the negative electrode,
The positive electrode includes a positive electrode molded body containing a positive electrode active material capable of inserting and extracting lithium,
The negative electrode includes a molded negative electrode including a negative electrode active material capable of occluding and releasing lithium,
The negative electrode molded body is a coin type having two flat portions and a side surface portion, and has a crack in the thickness direction, and the negative electrode can has a convex portion on a surface facing the negative electrode molded body. The coin-type lithium secondary battery, wherein the crack is a crack starting from a contact portion between the convex portion and the molded negative electrode. 前記凸部が、線状、円状、放射状、格子状、多角形状およびハニカム状よりなる群から選択される少なくとも１つのパターンで形成されている、請求項１０記載のコイン型リチウム二次電池。   The coin-type lithium secondary battery according to claim 10, wherein the convex portion is formed in at least one pattern selected from the group consisting of a linear shape, a circular shape, a radial shape, a lattice shape, a polygonal shape, and a honeycomb shape. 前記負極活物質が、遷移金属とＳｉとの合金、Ｓｉ、ＳｉＯx（０＜ｘ＜２）、ＳｎおよびＳｎＯx（０＜ｘ≦２）よりなる群から選択される少なくとも１種を含む、請求項１０記載のコイン型リチウム二次電池。 The negative electrode active material includes at least one selected from the group consisting of an alloy of transition metal and Si, Si, SiO x (0 <x <2), Sn, and SnO x (0 <x ≦ 2). The coin-type lithium secondary battery according to claim 10. （i）リチウムの吸蔵および放出が可能な負極活物質を含む負極合剤を調製し、
（ii）前記負極合剤を加圧成型して、２つの平面部と側面部とを有するコイン型の負極成型体を作製し、
（iii）前記負極成型体の厚さ方向に亀裂を形成する工程、を有するコイン型リチウム二次電池用負極の製造方法。 (I) preparing a negative electrode mixture containing a negative electrode active material capable of inserting and extracting lithium;
(Ii) pressure-molding the negative electrode mixture to produce a coin-shaped negative electrode molded body having two flat portions and side portions;
(Iii) A method for producing a negative electrode for a coin-type lithium secondary battery, comprising the step of forming a crack in the thickness direction of the negative electrode molded body. 前記負極成型体を作製する工程（ii）が、前記２つの平面部の少なくとも一方に凹部を形成する工程を含む、請求項１３記載のコイン型リチウム二次電池用負極の製造方法。   The method for producing a negative electrode for a coin-type lithium secondary battery according to claim 13, wherein the step (ii) of producing the molded negative electrode includes a step of forming a recess in at least one of the two flat portions. 前記亀裂を形成する工程（iii）が、前記負極成型体と対向する凸部を有する面を有する負極缶を供給し、前記負極成型体を、前記凸部を有する面に圧着する工程を含む、請求項１３記載のコイン型リチウム二次電池用負極の製造方法。   The step (iii) of forming the crack includes a step of supplying a negative electrode can having a surface having a convex portion facing the negative electrode molded body, and crimping the negative electrode molded body to the surface having the convex portion. The manufacturing method of the negative electrode for coin-type lithium secondary batteries of Claim 13. 前記亀裂を形成する工程（iii）が、凸部を有する治具で支持した前記負極成型体に、リチウム金属を圧着する工程を含む、請求項１３記載のコイン型リチウム二次電池用負極の製造方法。   14. The manufacture of a negative electrode for a coin-type lithium secondary battery according to claim 13, wherein the step (iii) of forming the crack includes a step of pressure bonding lithium metal to the molded negative electrode supported by a jig having a convex portion. Method. 前記亀裂を形成する工程（iii）が、凹部を有する治具で支持した前記負極成型体に、リチウム金属を圧着する工程を含む、請求項１３記載のコイン型リチウム二次電池用負極の製造方法。   The method for producing a negative electrode for a coin-type lithium secondary battery according to claim 13, wherein the step (iii) of forming the crack includes a step of pressure bonding lithium metal to the molded negative electrode supported by a jig having a recess. . 前記亀裂を形成する工程（iii）が、前記負極成型体と対向するリチウム金属を貼り付けた面を有する負極缶を供給し、凸部を有する治具で、前記負極成型体を押圧して、前記リチウム金属に前記負極成型体を圧着する工程を含む、請求項１３記載のコイン型リチウム二次電池用負極の製造方法。   The step (iii) of forming the crack supplies a negative electrode can having a surface to which a lithium metal facing the negative electrode molded body is attached, and presses the negative electrode molded body with a jig having a convex portion, The manufacturing method of the negative electrode for coin-type lithium secondary batteries of Claim 13 including the process of crimping | bonding the said negative electrode molded object to the said lithium metal. 前記亀裂を形成する工程（iii）が、前記負極成型体と対向するリチウム金属を貼り付けた面を有する負極缶を供給し、凹部を有する治具で、前記負極成型体を押圧して、前記リチウム金属に前記負極成型体を圧着する工程を含む、請求項１３記載のコイン型リチウム二次電池用負極の製造方法。   The step (iii) of forming the crack supplies a negative electrode can having a surface to which a lithium metal facing the negative electrode molded body is attached, and presses the negative electrode molded body with a jig having a recess, The manufacturing method of the negative electrode for coin-type lithium secondary batteries of Claim 13 including the process of crimping | bonding the said negative electrode molded object to lithium metal.
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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011090869A (en) * 2009-10-22 2011-05-06 Shin-Etsu Chemical Co Ltd Negative electrode material for nonaqueous electrolyte secondary battery, method of manufacturing the same, negative electrode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0432159A (en) * 1990-05-24 1992-02-04 Seiko Instr Inc Nonaqueous electrolytic secondary battery
JP2004103474A (en) * 2002-09-11 2004-04-02 Sony Corp Nonaqueous electrolyte battery and manufacturing method of the same
JP2004241256A (en) * 2003-02-06 2004-08-26 Matsushita Electric Ind Co Ltd Nonaqueous electrolyte secondary battery
JP2005222830A (en) * 2004-02-06 2005-08-18 Sony Corp Liquid electrolyte and battery

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0432159A (en) * 1990-05-24 1992-02-04 Seiko Instr Inc Nonaqueous electrolytic secondary battery
JP2004103474A (en) * 2002-09-11 2004-04-02 Sony Corp Nonaqueous electrolyte battery and manufacturing method of the same
JP2004241256A (en) * 2003-02-06 2004-08-26 Matsushita Electric Ind Co Ltd Nonaqueous electrolyte secondary battery
JP2005222830A (en) * 2004-02-06 2005-08-18 Sony Corp Liquid electrolyte and battery

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